Project acronym ANYONIC
Project Statistics of Exotic Fractional Hall States
Researcher (PI) Mordehai HEIBLUM
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2018-ADG
Summary Since their discovery, Quantum Hall Effects have unfolded intriguing avenues of research, exhibiting a multitude of unexpected exotic states: accurate quantized conductance states; particle-like and hole-conjugate fractional states; counter-propagating charge and neutral edge modes; and fractionally charged quasiparticles - abelian and (predicted) non-abelian. Since the sought-after anyonic statistics of fractional states is yet to be verified, I propose to launch a thorough search for it employing new means. I believe that our studies will serve the expanding field of the emerging family of topological materials.
Our on-going attempts to observe quasiparticles (qp’s) interference, in order to uncover their exchange statistics (under ERC), taught us that spontaneous, non-topological, ‘neutral edge modes’ are the main culprit responsible for qp’s dephasing. In an effort to quench the neutral modes, we plan to develop a new class of micro-size interferometers, based on synthetically engineered fractional modes. Flowing away from the fixed physical edge, their local environment can be controlled, making it less hospitable for the neutral modes.
Having at hand our synthetized helical-type fractional modes, it is highly tempting to employ them to form localize para-fermions, which will extend the family of exotic states. This can be done by proximitizing them to a superconductor, or gapping them via inter-mode coupling.
The less familiar thermal conductance measurements, which we recently developed (under ERC), will be applied throughout our work to identify ‘topological orders’ of exotic states; namely, distinguishing between abelian and non-abelian fractional states.
The proposal is based on an intensive and continuous MBE effort, aimed at developing extremely high purity, GaAs based, structures. Among them, structures that support our new synthetic modes that are amenable to manipulation, and others that host rare exotic states, such as v=5/2, 12/5, 19/8, and 35/16.
Summary
Since their discovery, Quantum Hall Effects have unfolded intriguing avenues of research, exhibiting a multitude of unexpected exotic states: accurate quantized conductance states; particle-like and hole-conjugate fractional states; counter-propagating charge and neutral edge modes; and fractionally charged quasiparticles - abelian and (predicted) non-abelian. Since the sought-after anyonic statistics of fractional states is yet to be verified, I propose to launch a thorough search for it employing new means. I believe that our studies will serve the expanding field of the emerging family of topological materials.
Our on-going attempts to observe quasiparticles (qp’s) interference, in order to uncover their exchange statistics (under ERC), taught us that spontaneous, non-topological, ‘neutral edge modes’ are the main culprit responsible for qp’s dephasing. In an effort to quench the neutral modes, we plan to develop a new class of micro-size interferometers, based on synthetically engineered fractional modes. Flowing away from the fixed physical edge, their local environment can be controlled, making it less hospitable for the neutral modes.
Having at hand our synthetized helical-type fractional modes, it is highly tempting to employ them to form localize para-fermions, which will extend the family of exotic states. This can be done by proximitizing them to a superconductor, or gapping them via inter-mode coupling.
The less familiar thermal conductance measurements, which we recently developed (under ERC), will be applied throughout our work to identify ‘topological orders’ of exotic states; namely, distinguishing between abelian and non-abelian fractional states.
The proposal is based on an intensive and continuous MBE effort, aimed at developing extremely high purity, GaAs based, structures. Among them, structures that support our new synthetic modes that are amenable to manipulation, and others that host rare exotic states, such as v=5/2, 12/5, 19/8, and 35/16.
Max ERC Funding
1 801 094 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym BIOSELFORGANIZATION
Project Biophysical aspects of self-organization in actin-based cell motility
Researcher (PI) Kinneret Magda Keren
Host Institution (HI) TECHNION - ISRAEL INSTITUTE OF TECHNOLOGY
Call Details Starting Grant (StG), PE3, ERC-2007-StG
Summary Cell motility is a fascinating dynamic process crucial for a wide variety of biological phenomena including defense against injury or infection, embryogenesis and cancer metastasis. A spatially extended, self-organized, mechanochemical machine consisting of numerous actin polymers, accessory proteins and molecular motors drives this process. This impressive assembly self-organizes over several orders of magnitude in both the temporal and spatial domains bridging from the fast dynamics of individual molecular-sized building blocks to the persistent motion of whole cells over minutes and hours. The molecular players involved in the process and the basic biochemical mechanisms are largely known. However, the principles governing the assembly of the motility apparatus, which involve an intricate interplay between biophysical processes and biochemical reactions, are still poorly understood. The proposed research is focused on investigating the biophysical aspects of the self-organization processes underlying cell motility and trying to adapt these processes to instill motility in artificial cells. Important biophysical characteristics of moving cells such as the intracellular fluid flow and membrane tension will be measured and their effect on the motility process will be examined, using fish epithelial keratocytes as a model system. The dynamics of the system will be further investigated by quantitatively analyzing the morphological and kinematic variation displayed by a population of cells and by an individual cell through time. Such measurements will feed into and direct the development of quantitative theoretical models. In parallel, I will work toward the development of a synthetic physical model system for cell motility by encapsulating the actin machinery in a cell-sized compartment. This synthetic system will allow cell motility to be studied in a simplified and controlled environment, detached from the complexity of the living cell.
Summary
Cell motility is a fascinating dynamic process crucial for a wide variety of biological phenomena including defense against injury or infection, embryogenesis and cancer metastasis. A spatially extended, self-organized, mechanochemical machine consisting of numerous actin polymers, accessory proteins and molecular motors drives this process. This impressive assembly self-organizes over several orders of magnitude in both the temporal and spatial domains bridging from the fast dynamics of individual molecular-sized building blocks to the persistent motion of whole cells over minutes and hours. The molecular players involved in the process and the basic biochemical mechanisms are largely known. However, the principles governing the assembly of the motility apparatus, which involve an intricate interplay between biophysical processes and biochemical reactions, are still poorly understood. The proposed research is focused on investigating the biophysical aspects of the self-organization processes underlying cell motility and trying to adapt these processes to instill motility in artificial cells. Important biophysical characteristics of moving cells such as the intracellular fluid flow and membrane tension will be measured and their effect on the motility process will be examined, using fish epithelial keratocytes as a model system. The dynamics of the system will be further investigated by quantitatively analyzing the morphological and kinematic variation displayed by a population of cells and by an individual cell through time. Such measurements will feed into and direct the development of quantitative theoretical models. In parallel, I will work toward the development of a synthetic physical model system for cell motility by encapsulating the actin machinery in a cell-sized compartment. This synthetic system will allow cell motility to be studied in a simplified and controlled environment, detached from the complexity of the living cell.
Max ERC Funding
900 000 €
Duration
Start date: 2008-08-01, End date: 2013-07-31
Project acronym CCICO
Project Coupled and Competing Instabilities in Complex Oxides
Researcher (PI) Nicola Ann Spaldin
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary "The CCICO project will build a comprehensive understanding of how proximity to previously unexplored combinations of instabilities, as well as previously unidentified types of ordering, manifest in novel behaviors, and will develop design guidelines for practical realization of new materials with such behaviors. Taking transition-metal oxides as our model systems, we will develop and apply first-principles electronic structure theory methods to explore an extensive array of new combinations of orderings, with a focus on interactions between the electronic -- Jahn-Teller, orbital and charge -- and structural -- rotations, ferroelectric and other distortions -- degrees of freedom. Our goal is to spawn a new field of study based on a novel combination of orderings in the same way that the field of multiferroics was jump-started ten years ago by our work understanding the coexistence of ferroelectricity and magnetism. Conversely, we will apply the computational tools developed in our history of studying multiferroics, particularly descriptions of proximity to structural and magnetic phase transitions, to characterizing observed behaviors such as exotic superconductivity in existing materials. In the process we will search for and characterize elusive or poorly characterized forms of order in solids, with a focus on ferrotoroidicity and emergent local dipoles. A final application is to create designer materials for solid-state experiments relevant to high-energy physics and cosmology. Promising compounds that are amenable to bulk synthesis will be made in our new oxide single-crystal growth laboratory; materials that require thin-film routes will be pursued in collaboration with colleagues."
Summary
"The CCICO project will build a comprehensive understanding of how proximity to previously unexplored combinations of instabilities, as well as previously unidentified types of ordering, manifest in novel behaviors, and will develop design guidelines for practical realization of new materials with such behaviors. Taking transition-metal oxides as our model systems, we will develop and apply first-principles electronic structure theory methods to explore an extensive array of new combinations of orderings, with a focus on interactions between the electronic -- Jahn-Teller, orbital and charge -- and structural -- rotations, ferroelectric and other distortions -- degrees of freedom. Our goal is to spawn a new field of study based on a novel combination of orderings in the same way that the field of multiferroics was jump-started ten years ago by our work understanding the coexistence of ferroelectricity and magnetism. Conversely, we will apply the computational tools developed in our history of studying multiferroics, particularly descriptions of proximity to structural and magnetic phase transitions, to characterizing observed behaviors such as exotic superconductivity in existing materials. In the process we will search for and characterize elusive or poorly characterized forms of order in solids, with a focus on ferrotoroidicity and emergent local dipoles. A final application is to create designer materials for solid-state experiments relevant to high-energy physics and cosmology. Promising compounds that are amenable to bulk synthesis will be made in our new oxide single-crystal growth laboratory; materials that require thin-film routes will be pursued in collaboration with colleagues."
Max ERC Funding
2 000 000 €
Duration
Start date: 2012-03-01, End date: 2017-02-28
Project acronym CEMAS
Project Controlling and Exploring Molecular Systems at the Atomic Scale with Atomic Force Microscopy
Researcher (PI) Gerhard Meyer
Host Institution (HI) IBM RESEARCH GMBH
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary The objective of this project is to advance and use Atomic Force Microscopy (AFM) to explore the physical and chemical properties of single molecules and molecular systems with unprecedented spatial resolution. We will use AFM to develop atomically resolved molecular imaging with structural and chemical identification and investigate charge distribution and transfer in molecular systems. The AFM will allow the extension of seminal Scanning Tunneling Microscopy (STM) work on atoms/molecules on ultra-thin insulating films to thick insulating films, to control and explore single molecule chemistry processes in utmost detail. The whole work will be significantly based on the development and exploitation of novel atomic and molecular manipulation processes to control matter at the atomic scale, both for fabricating novel complex molecular nanostructures with atomic scale precision and understanding these systems, as well as for probe-tip functionalization to tailor tip-substrate interaction. Instrumental enhancements will focus on fabricating novel AFM sensors for simultaneous lateral and vertical force measurement and on developing a new original approach to increase the time resolution in AFM measurements. Due to the fundamental nature of this work we expect the long term impact of this work to be in surface science, chemistry, molecular electronics and life sciences. In the short term we expect to develop the AFM into a practical tool for chemical structure determination of unknown molecules and we will employ atomic manipulation and high resolution AFM imaging to image, modify and functionalize graphene edge structures with atomic scale precision with the prospect of exploring and developing novel molecular devices.
Summary
The objective of this project is to advance and use Atomic Force Microscopy (AFM) to explore the physical and chemical properties of single molecules and molecular systems with unprecedented spatial resolution. We will use AFM to develop atomically resolved molecular imaging with structural and chemical identification and investigate charge distribution and transfer in molecular systems. The AFM will allow the extension of seminal Scanning Tunneling Microscopy (STM) work on atoms/molecules on ultra-thin insulating films to thick insulating films, to control and explore single molecule chemistry processes in utmost detail. The whole work will be significantly based on the development and exploitation of novel atomic and molecular manipulation processes to control matter at the atomic scale, both for fabricating novel complex molecular nanostructures with atomic scale precision and understanding these systems, as well as for probe-tip functionalization to tailor tip-substrate interaction. Instrumental enhancements will focus on fabricating novel AFM sensors for simultaneous lateral and vertical force measurement and on developing a new original approach to increase the time resolution in AFM measurements. Due to the fundamental nature of this work we expect the long term impact of this work to be in surface science, chemistry, molecular electronics and life sciences. In the short term we expect to develop the AFM into a practical tool for chemical structure determination of unknown molecules and we will employ atomic manipulation and high resolution AFM imaging to image, modify and functionalize graphene edge structures with atomic scale precision with the prospect of exploring and developing novel molecular devices.
Max ERC Funding
2 496 720 €
Duration
Start date: 2011-12-01, End date: 2016-11-30
Project acronym CONQUEST
Project Controlled quantum effects and spin technology
- from non-equilibrium physics to functional magnetics
Researcher (PI) Henrik Ronnow
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Starting Grant (StG), PE3, ERC-2010-StG_20091028
Summary The technology of the 20th century was dominated by a single material class: The semiconductors, whose properties can be tuned between those of metals and insulators all of which describable by single-electron effects. In contrast, quantum magnets and strongly correlated electron systems offer a full palette of quantum mechanical many-electron states. CONQUEST aim to discover, understand and demonstrate control over such quantum states. A new experimental approach, building on established powerful laboratory and neutron scattering techniques combined with dynamical control-perturbations, will be developed to study correlated quantum effects in magnetic materials. The immediate goal is to open a new field of non-equilibrium and time dependent studies in solid state physics. The long-term vision is that the approach might nurture the materials of the 21st century.
Summary
The technology of the 20th century was dominated by a single material class: The semiconductors, whose properties can be tuned between those of metals and insulators all of which describable by single-electron effects. In contrast, quantum magnets and strongly correlated electron systems offer a full palette of quantum mechanical many-electron states. CONQUEST aim to discover, understand and demonstrate control over such quantum states. A new experimental approach, building on established powerful laboratory and neutron scattering techniques combined with dynamical control-perturbations, will be developed to study correlated quantum effects in magnetic materials. The immediate goal is to open a new field of non-equilibrium and time dependent studies in solid state physics. The long-term vision is that the approach might nurture the materials of the 21st century.
Max ERC Funding
1 500 000 €
Duration
Start date: 2011-04-01, End date: 2016-03-31
Project acronym COSPSENA
Project Coherence of Spins in Semiconductor Nanostructures
Researcher (PI) Dominik Max Zumbühl
Host Institution (HI) UNIVERSITAT BASEL
Call Details Starting Grant (StG), PE3, ERC-2007-StG
Summary Macroscopic control of quantum states is a major theme in much of modern physics because quantum coherence enables study of fundamental physics and has promising applications for quantum information processing. The potential significance of quantum computing is recognized well beyond the physics community. For electron spins in GaAs quantum dots, it has become clear that decoherence caused by interactions with the nuclear spins is a major challenge. We propose to investigate and reduce hyperfine induced decoherence with two complementary approaches: nuclear spin state narrowing and nuclear spin polarization. We propose a new projective state narrowing technique: a large, Coulomb blockaded dot measures the qubit nuclear ensemble, resulting in enhanced spin coherence times. Further, mediated by an interacting 2D electron gas via hyperfine interaction, a low temperature nuclear ferromagnetic spin state was predicted, which we propose to investigate using a quantum point contact as a nuclear polarization detector. Estimates indicate that the nuclear ferromagnetic transition occurs in the sub-Millikelvin range, well below already hard to reach temperatures around 10 mK. However, the exciting combination of interacting electron and nuclear spin physics as well as applications in spin qubits give ample incentive to strive for sub-Millikelvin temperatures in nanostructures. We propose to build a novel type of nuclear demagnetization refrigerator aiming to reach electron temperatures of 0.1 mK in semiconductor nanostructures. This interdisciplinary project combines Microkelvin and nanophysics, going well beyond the status quo. It is a challenging project that could be the beginning of a new era of coherent spin physics with unprecedented quantum control. This project requires a several year commitment and a team of two graduate students plus one postdoctoral fellow.
Summary
Macroscopic control of quantum states is a major theme in much of modern physics because quantum coherence enables study of fundamental physics and has promising applications for quantum information processing. The potential significance of quantum computing is recognized well beyond the physics community. For electron spins in GaAs quantum dots, it has become clear that decoherence caused by interactions with the nuclear spins is a major challenge. We propose to investigate and reduce hyperfine induced decoherence with two complementary approaches: nuclear spin state narrowing and nuclear spin polarization. We propose a new projective state narrowing technique: a large, Coulomb blockaded dot measures the qubit nuclear ensemble, resulting in enhanced spin coherence times. Further, mediated by an interacting 2D electron gas via hyperfine interaction, a low temperature nuclear ferromagnetic spin state was predicted, which we propose to investigate using a quantum point contact as a nuclear polarization detector. Estimates indicate that the nuclear ferromagnetic transition occurs in the sub-Millikelvin range, well below already hard to reach temperatures around 10 mK. However, the exciting combination of interacting electron and nuclear spin physics as well as applications in spin qubits give ample incentive to strive for sub-Millikelvin temperatures in nanostructures. We propose to build a novel type of nuclear demagnetization refrigerator aiming to reach electron temperatures of 0.1 mK in semiconductor nanostructures. This interdisciplinary project combines Microkelvin and nanophysics, going well beyond the status quo. It is a challenging project that could be the beginning of a new era of coherent spin physics with unprecedented quantum control. This project requires a several year commitment and a team of two graduate students plus one postdoctoral fellow.
Max ERC Funding
1 377 000 €
Duration
Start date: 2008-06-01, End date: 2013-05-31
Project acronym DYNCORSYS
Project Real-time dynamics of correlated many-body systems
Researcher (PI) Philipp Werner
Host Institution (HI) UNIVERSITE DE FRIBOURG
Call Details Starting Grant (StG), PE3, ERC-2011-StG_20101014
Summary "Strongly correlated materials exhibit some of the most remarkable phenonomena found in condensed matter systems. They typically involve many active degrees of freedom (spin, charge, orbital), which leads to numerous competing states and complicated phase diagrams. A new perspective on correlated many-body systems is provided by the nonequilibrium dynamics, which is being explored in transport studies on nanostructures, pump-probe experiments on correlated solids, and in quench experiments on ultra-cold atomic gases.
An advanced theoretical framework for the study of correlated lattice models, which can be adapted to nonequilibrium situations, is dynamical mean field theory (DMFT). One aim of this proposal is to develop ""nonequilibrium DMFT"" into a powerful tool for the simulation of excitation and relaxation processes in interacting many-body systems. The big challenge in these simulations is the calculation of the real-time evolution of a quantum impurity model. Recently developed real-time impurity solvers have, however, opened the door to a wide range of applications. We will improve the efficiency and flexibility of these methods and develop complementary approaches, which will extend the accessible parameter regimes. This machinery will be used to study correlated lattice models under nonequilibrium conditions. The ultimate goal is to explore and qualitatively understand the nonequilibrium properties of ""real"" materials with active spin, charge, orbital and lattice degrees of freedom.
The ability to simulate the real-time dynamics of correlated many-body systems will be crucial for the interpretation of experiments and the discovery of correlation effects which manifest themselves only in the form of transient states. A proper understanding of the most basic nonequilibrium phenomena in correlated solids will help guide future experiments and hopefully lead to new technological applications such as ultra-fast switches or storage devices."
Summary
"Strongly correlated materials exhibit some of the most remarkable phenonomena found in condensed matter systems. They typically involve many active degrees of freedom (spin, charge, orbital), which leads to numerous competing states and complicated phase diagrams. A new perspective on correlated many-body systems is provided by the nonequilibrium dynamics, which is being explored in transport studies on nanostructures, pump-probe experiments on correlated solids, and in quench experiments on ultra-cold atomic gases.
An advanced theoretical framework for the study of correlated lattice models, which can be adapted to nonequilibrium situations, is dynamical mean field theory (DMFT). One aim of this proposal is to develop ""nonequilibrium DMFT"" into a powerful tool for the simulation of excitation and relaxation processes in interacting many-body systems. The big challenge in these simulations is the calculation of the real-time evolution of a quantum impurity model. Recently developed real-time impurity solvers have, however, opened the door to a wide range of applications. We will improve the efficiency and flexibility of these methods and develop complementary approaches, which will extend the accessible parameter regimes. This machinery will be used to study correlated lattice models under nonequilibrium conditions. The ultimate goal is to explore and qualitatively understand the nonequilibrium properties of ""real"" materials with active spin, charge, orbital and lattice degrees of freedom.
The ability to simulate the real-time dynamics of correlated many-body systems will be crucial for the interpretation of experiments and the discovery of correlation effects which manifest themselves only in the form of transient states. A proper understanding of the most basic nonequilibrium phenomena in correlated solids will help guide future experiments and hopefully lead to new technological applications such as ultra-fast switches or storage devices."
Max ERC Funding
1 493 178 €
Duration
Start date: 2012-02-01, End date: 2017-01-31
Project acronym ETOPEX
Project Engineering Topological Phases and Excitations in Nanostructures with Interactions
Researcher (PI) Jelena KLINOVAJA
Host Institution (HI) UNIVERSITAT BASEL
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary The main goal of this theory project is to propose engineered topological phases emerging only in strongly interacting systems and to identify the most feasible systems for experimental implementation. First, we will focus on setups hosting topological states localized at domain walls in one-dimensional channels such as parafermions, which are a new class of non-Abelian anyons and most promising candidates for topological quantum computing schemes. Second, in the framework of weakly coupled wires and planes, we will develop schemes for novel fractional topological phases in two- and three-dimensional interacting systems. To achieve these two goals, my team will identify necessary ingredients such as strong electron-electron interactions, helical magnetic order, or crossed Andreev proximity-induced superconductivity and address each of them separately. Later, we combine them to lead us to the desired topological phases and states. On our way to the main goal, as test cases, we will also study non-interacting analogies of the proposed effects such as Majorana fermions and integer topological insulators and pay close attention to the rapid experimental progress to come up with the most feasible proposals. We will study transport properties, scanning tunneling and atomic force microscopy. Especially for systems driven out of equilibrium, we will develop a Floquet-Luttinger liquid technique. We will explore the stability of engineered topological phases, error rates of topological qubits based on them, and computation schemes allowing for a set of universal qubit gates. We will strive to find a reasonable balance between topological stability and experimental
feasibility of setups. Our main theoretical tools are Luttinger liquid techniques (bosonization and renormalization group), Green functions, Floquet formalism, and numerical simulations in non-interacting test models.
Summary
The main goal of this theory project is to propose engineered topological phases emerging only in strongly interacting systems and to identify the most feasible systems for experimental implementation. First, we will focus on setups hosting topological states localized at domain walls in one-dimensional channels such as parafermions, which are a new class of non-Abelian anyons and most promising candidates for topological quantum computing schemes. Second, in the framework of weakly coupled wires and planes, we will develop schemes for novel fractional topological phases in two- and three-dimensional interacting systems. To achieve these two goals, my team will identify necessary ingredients such as strong electron-electron interactions, helical magnetic order, or crossed Andreev proximity-induced superconductivity and address each of them separately. Later, we combine them to lead us to the desired topological phases and states. On our way to the main goal, as test cases, we will also study non-interacting analogies of the proposed effects such as Majorana fermions and integer topological insulators and pay close attention to the rapid experimental progress to come up with the most feasible proposals. We will study transport properties, scanning tunneling and atomic force microscopy. Especially for systems driven out of equilibrium, we will develop a Floquet-Luttinger liquid technique. We will explore the stability of engineered topological phases, error rates of topological qubits based on them, and computation schemes allowing for a set of universal qubit gates. We will strive to find a reasonable balance between topological stability and experimental
feasibility of setups. Our main theoretical tools are Luttinger liquid techniques (bosonization and renormalization group), Green functions, Floquet formalism, and numerical simulations in non-interacting test models.
Max ERC Funding
1 158 403 €
Duration
Start date: 2018-01-01, End date: 2022-12-31
Project acronym ExCOM-cCEO
Project Extremely Coherent Mechanical Oscillators and circuit Cavity Electro-Optics
Researcher (PI) Tobias Kippenberg
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Advanced Grant (AdG), PE3, ERC-2018-ADG
Summary The quest for mechanical oscillators with ultralow dissipation is motivated by classical and quantum sensing and technology, and precision measurements. For decades, the most coherent mechanical oscillators were acoustic vibrations in kg-scale crystalline bars. Recently a paradigm shift has occurred. The combination of elastic strain engineering – a technique used in microelectronics – with phononic mode engineering has resulted in 1D nano-strings with a mechanical quality factor Q of 0.8 billion – the highest ever achieved at room temperature. Remarkably, these new techniques have major untapped potential, as they have only been applied to non-crystalline materials in 1D. We propose a new generation of strain-engineered crystalline and superconducting mechanical oscillators whose Q-factors are predicted to exceed 100 billion in up to 2 dimensions. We will seek to reach this theoretical limit, probe new dissipation mechanisms, and utilize these oscillators for quantum optomechanics in new regimes and achieve room temperature ground state cooling and ponderomotive squeezing. Likewise, we will apply these techniques to create highly coherent superconducting electromechanical devices at milli-Kelvin temperatures, enabling quantum-enhanced force sensing and 1 second decoherence times. Secondly, we will explore a fundamentally new method for measurement and manipulation of microwave fields with optical fields – the nascent field of circuit Cavity-Electro-Optics (cCEO). First recognized over a decade ago, it is possible with optical fields to cool, amplify or interferometrically read out microwaves. Yet to date this regime has remained in accessible due to insufficient coupling strength between the microwave and optical fields. We will overcome this challenge based on a new circuit architecture, allowing laser cooling and laser amplification of microwaves and electro-optical masing using optical backaction, and thereby opening an entirely new way to manipulate microwaves.
Summary
The quest for mechanical oscillators with ultralow dissipation is motivated by classical and quantum sensing and technology, and precision measurements. For decades, the most coherent mechanical oscillators were acoustic vibrations in kg-scale crystalline bars. Recently a paradigm shift has occurred. The combination of elastic strain engineering – a technique used in microelectronics – with phononic mode engineering has resulted in 1D nano-strings with a mechanical quality factor Q of 0.8 billion – the highest ever achieved at room temperature. Remarkably, these new techniques have major untapped potential, as they have only been applied to non-crystalline materials in 1D. We propose a new generation of strain-engineered crystalline and superconducting mechanical oscillators whose Q-factors are predicted to exceed 100 billion in up to 2 dimensions. We will seek to reach this theoretical limit, probe new dissipation mechanisms, and utilize these oscillators for quantum optomechanics in new regimes and achieve room temperature ground state cooling and ponderomotive squeezing. Likewise, we will apply these techniques to create highly coherent superconducting electromechanical devices at milli-Kelvin temperatures, enabling quantum-enhanced force sensing and 1 second decoherence times. Secondly, we will explore a fundamentally new method for measurement and manipulation of microwave fields with optical fields – the nascent field of circuit Cavity-Electro-Optics (cCEO). First recognized over a decade ago, it is possible with optical fields to cool, amplify or interferometrically read out microwaves. Yet to date this regime has remained in accessible due to insufficient coupling strength between the microwave and optical fields. We will overcome this challenge based on a new circuit architecture, allowing laser cooling and laser amplification of microwaves and electro-optical masing using optical backaction, and thereby opening an entirely new way to manipulate microwaves.
Max ERC Funding
2 496 000 €
Duration
Start date: 2019-10-01, End date: 2024-09-30
Project acronym FACT
Project Factorizing the wave function of large quantum systems
Researcher (PI) Eberhard Gross
Host Institution (HI) THE HEBREW UNIVERSITY OF JERUSALEM
Call Details Advanced Grant (AdG), PE3, ERC-2017-ADG
Summary This proposal puts forth a novel strategy to tackle large quantum systems. A variety of highly sophisticated methods such as quantum Monte Carlo, configuration interaction, coupled cluster, tensor networks, Feynman diagrams, dynamical mean-field theory, density functional theory, and semi-classical techniques have been developed to deal with the enormous complexity of the many-particle Schrödinger equation. The goal of our proposal is not to add another method to these standard techniques but, instead, we develop a systematic way of combining them. The essential ingredient is a novel way of decomposing the wave function without approximation into factors that describe subsystems of the full quantum system. This so-called exact factorization is asymmetric. In the case of two subsystems, one factor is a wave function satisfying a regular Schrödinger equation, while the other factor is a conditional probability amplitude satisfying a more complicated Schrödinger-like equation with a non-local, non-linear and non-Hermitian “Hamiltonian”. Since each subsystem is necessarily smaller than the full system, the above standard techniques can be applied more efficiently and, most importantly, different standard techniques can be applied to different subsystems. The power of the exact factorization lies in its versatility. Here we apply the technique to five different scenarios: The first two deal with non-adiabatic effects in (i) molecules and (ii) solids. Here the natural subsystems are electrons and nuclei. The third scenario deals with nuclear motion in (iii) molecules attached to semi-infinite metallic leads, requiring three subsystems: the electrons, the nuclei in the leads which ultimately reduce to a phonon bath, and the molecular nuclei which may perform large-amplitude movements, such as current-induced isomerization, (iv) purely electronic correlations, and (v) the interaction of matter with the quantized electromagnetic field, i.e., electrons, nuclei and photons.
Summary
This proposal puts forth a novel strategy to tackle large quantum systems. A variety of highly sophisticated methods such as quantum Monte Carlo, configuration interaction, coupled cluster, tensor networks, Feynman diagrams, dynamical mean-field theory, density functional theory, and semi-classical techniques have been developed to deal with the enormous complexity of the many-particle Schrödinger equation. The goal of our proposal is not to add another method to these standard techniques but, instead, we develop a systematic way of combining them. The essential ingredient is a novel way of decomposing the wave function without approximation into factors that describe subsystems of the full quantum system. This so-called exact factorization is asymmetric. In the case of two subsystems, one factor is a wave function satisfying a regular Schrödinger equation, while the other factor is a conditional probability amplitude satisfying a more complicated Schrödinger-like equation with a non-local, non-linear and non-Hermitian “Hamiltonian”. Since each subsystem is necessarily smaller than the full system, the above standard techniques can be applied more efficiently and, most importantly, different standard techniques can be applied to different subsystems. The power of the exact factorization lies in its versatility. Here we apply the technique to five different scenarios: The first two deal with non-adiabatic effects in (i) molecules and (ii) solids. Here the natural subsystems are electrons and nuclei. The third scenario deals with nuclear motion in (iii) molecules attached to semi-infinite metallic leads, requiring three subsystems: the electrons, the nuclei in the leads which ultimately reduce to a phonon bath, and the molecular nuclei which may perform large-amplitude movements, such as current-induced isomerization, (iv) purely electronic correlations, and (v) the interaction of matter with the quantized electromagnetic field, i.e., electrons, nuclei and photons.
Max ERC Funding
2 443 932 €
Duration
Start date: 2019-09-01, End date: 2024-08-31
Project acronym FFlowCCS
Project Fluid Flow in Complex and Curved Spaces
Researcher (PI) Hans Jürgen Herrmann
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2012-ADG_20120216
Summary In many natural and industrial situations, fluids in cavities, membranes or pipes of complex shape grow as well as modify the structures through which they flow. This leads to important challenges both fundamental, like biological morphogenesis, and practical, like the motion of nano-electromechanical systems (NEMS). We seek to substantially advance the understanding of the resulting shapes and instabilities. Our approach will focus on numerical methods, validated through theoretical and experimental analysis.
Mathematically fluid-structure interactions involve ambitious moving boundary problems, where structure and fluid flow feedback on one another in complex ways. Detailed analysis requires precise modeling of coupling between very strongly de¬forming elasto-plastic solids and fluid flow in intricately curved spaces and solving both iteratively many times. To address this computational challenge, significant innovations will be implemented, including the use of novel erosion laws, the insertion of spatial curvature and metric directly into the equations of motion of the fluid, and special methods to handle the singular behaviour at kinks and constrictions. Our fluid solvers will be new variants of Lattice Boltzmann Models (LBM) coupled to temperature and concentration fields. The accuracy of the methods will be quantitatively validated by experiments.
An unconventional hydrodynamic formulation for electronic currents will provide big advantages. We will develop LBM solvers for quantum and relativistic fluids and in particular create a Lattice Wigner model and couple it to the molecular dynamics of the support.
Our method will open new horizons for the design of continuously regenerating filters, for shape optimi¬zation of heat exchangers and catalysts and for the engineering of electronic devices. Our approach will also shed light on sand avalanches in oil extraction, on aspects of folding in living matter, and on electromechanical instabilities.
Summary
In many natural and industrial situations, fluids in cavities, membranes or pipes of complex shape grow as well as modify the structures through which they flow. This leads to important challenges both fundamental, like biological morphogenesis, and practical, like the motion of nano-electromechanical systems (NEMS). We seek to substantially advance the understanding of the resulting shapes and instabilities. Our approach will focus on numerical methods, validated through theoretical and experimental analysis.
Mathematically fluid-structure interactions involve ambitious moving boundary problems, where structure and fluid flow feedback on one another in complex ways. Detailed analysis requires precise modeling of coupling between very strongly de¬forming elasto-plastic solids and fluid flow in intricately curved spaces and solving both iteratively many times. To address this computational challenge, significant innovations will be implemented, including the use of novel erosion laws, the insertion of spatial curvature and metric directly into the equations of motion of the fluid, and special methods to handle the singular behaviour at kinks and constrictions. Our fluid solvers will be new variants of Lattice Boltzmann Models (LBM) coupled to temperature and concentration fields. The accuracy of the methods will be quantitatively validated by experiments.
An unconventional hydrodynamic formulation for electronic currents will provide big advantages. We will develop LBM solvers for quantum and relativistic fluids and in particular create a Lattice Wigner model and couple it to the molecular dynamics of the support.
Our method will open new horizons for the design of continuously regenerating filters, for shape optimi¬zation of heat exchangers and catalysts and for the engineering of electronic devices. Our approach will also shed light on sand avalanches in oil extraction, on aspects of folding in living matter, and on electromechanical instabilities.
Max ERC Funding
2 200 000 €
Duration
Start date: 2013-01-01, End date: 2017-12-31
Project acronym FIELDGRADIENTS
Project Phase Transitions and Chemical Reactions in Electric Field Gradients
Researcher (PI) Yoav Tsori
Host Institution (HI) BEN-GURION UNIVERSITY OF THE NEGEV
Call Details Starting Grant (StG), PE3, ERC-2010-StG_20091028
Summary We will study phase transitions and chemical and biological reactions in liquid mixtures
in electric field gradients. These new phase transitions are essential in statistical
physics and thermodynamics. We will examine theoretically the complex and yet unexplored
phase ordering dynamics in which droplets nucleate and move under the external nonuniform
force. We will look in detail at the interfacial instabilities which develop when the
field is increased. We will investigate how time-varying potentials produce
electromagnetic waves and how their spatial decay in the bistable liquid leads to phase
changes.
These transitions open a new and general way to control the spatio-temporal behaviour of
chemical reactions by directly manipulating the solvents' concentrations. When two or more
reagents are preferentially soluble in one of the mixture's components, field-induced
phase separation leads to acceleration of the reaction. When the reagents are soluble in
different solvents, field-induced demixing will lead to the reaction taking place at a
slow rate and at a two-dimensional surface. Additionally, the electric field allows us to
turn the reaction on or off. The numerical study and simulations will be complemented by
experiments. We will study theoretically and experimentally biochemical reactions. We will
find how actin-related structures are affected by field gradients. Using an electric field
as a tool we will control the rate of actin polymerisation. We will investigate if an
external field can damage cancer cells by disrupting their actin-related activity. The above
phenomena will be studied in a microfluidics environment. We will elucidate the separation
hydrodynamics occurring when thermodynamically miscible liquids flow in a channel and how
electric fields can reversibly create and destroy optical interfaces, as is relevant in
optofluidics. Chemical and biological reactions will be examined in the context of
lab-on-a-chip.
Summary
We will study phase transitions and chemical and biological reactions in liquid mixtures
in electric field gradients. These new phase transitions are essential in statistical
physics and thermodynamics. We will examine theoretically the complex and yet unexplored
phase ordering dynamics in which droplets nucleate and move under the external nonuniform
force. We will look in detail at the interfacial instabilities which develop when the
field is increased. We will investigate how time-varying potentials produce
electromagnetic waves and how their spatial decay in the bistable liquid leads to phase
changes.
These transitions open a new and general way to control the spatio-temporal behaviour of
chemical reactions by directly manipulating the solvents' concentrations. When two or more
reagents are preferentially soluble in one of the mixture's components, field-induced
phase separation leads to acceleration of the reaction. When the reagents are soluble in
different solvents, field-induced demixing will lead to the reaction taking place at a
slow rate and at a two-dimensional surface. Additionally, the electric field allows us to
turn the reaction on or off. The numerical study and simulations will be complemented by
experiments. We will study theoretically and experimentally biochemical reactions. We will
find how actin-related structures are affected by field gradients. Using an electric field
as a tool we will control the rate of actin polymerisation. We will investigate if an
external field can damage cancer cells by disrupting their actin-related activity. The above
phenomena will be studied in a microfluidics environment. We will elucidate the separation
hydrodynamics occurring when thermodynamically miscible liquids flow in a channel and how
electric fields can reversibly create and destroy optical interfaces, as is relevant in
optofluidics. Chemical and biological reactions will be examined in the context of
lab-on-a-chip.
Max ERC Funding
1 482 200 €
Duration
Start date: 2010-08-01, End date: 2015-07-31
Project acronym FLATRONICS
Project Electronic devices based on nanolayers
Researcher (PI) Andras Kis
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Starting Grant (StG), PE3, ERC-2009-StG
Summary The main objective of this research proposal is to explore the electrical properties of nanoscale devices and circuits based on nanolayers. Nanolayers cover a wide span of possible electronic properties, ranging from semiconducting to superconducting. The possibility to form electrical circuits by varying their geometry offers rich research and practical opportunities. Together with graphene, nanolayers could form the material library for future nanoelectronics where different materials could be mixed and matched to different functionalities.
Summary
The main objective of this research proposal is to explore the electrical properties of nanoscale devices and circuits based on nanolayers. Nanolayers cover a wide span of possible electronic properties, ranging from semiconducting to superconducting. The possibility to form electrical circuits by varying their geometry offers rich research and practical opportunities. Together with graphene, nanolayers could form the material library for future nanoelectronics where different materials could be mixed and matched to different functionalities.
Max ERC Funding
1 799 996 €
Duration
Start date: 2009-09-01, End date: 2014-08-31
Project acronym FQHE
Project Statistics of Fractionally Charged Quasi-Particles
Researcher (PI) Mordehai (Moty) Heiblum
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2008-AdG
Summary The discovery of the fractional quantum Hall effect created a revolution in solid state research by introducing a new state of matter resulting from strong electron interactions. The new state is characterized by excitations (quasi-particles) that carry fractional charge, which are expected to obey fractional statistics. While odd denominator fractional states are expected to have an abelian statistics, the newly discovered 5/2 even denominator fractional state is expected to have a non-abelian statistics. Moreover, a large number of emerging proposals predict that the latter state can be employed for topological quantum computing ( Station Q was founded by Microsoft Corp. in order to pursue this goal). This proposal aims at studying the abelian and non-abelian fractional charges, and in particular to observe their peculiar statistics. While charges are preferably determined by measuring quantum shot noise, their statistics must be determined via interference experiments, where one particle goes around another. The experiments are very demanding since the even denominator fractions turn to be very fragile and thus can be observed only in the purest possible two dimensional electron gas and at the lowest temperatures. While until very recently such high quality samples were available only by a single grower (in the USA), we have the capability now to grow extremely pure samples with profound even denominator states. As will be detailed in the proposal, we have all the necessary tools to study charge and statistics of these fascinating excitations, due to our experience in crystal growth, shot noise and interferometry measurements.
Summary
The discovery of the fractional quantum Hall effect created a revolution in solid state research by introducing a new state of matter resulting from strong electron interactions. The new state is characterized by excitations (quasi-particles) that carry fractional charge, which are expected to obey fractional statistics. While odd denominator fractional states are expected to have an abelian statistics, the newly discovered 5/2 even denominator fractional state is expected to have a non-abelian statistics. Moreover, a large number of emerging proposals predict that the latter state can be employed for topological quantum computing ( Station Q was founded by Microsoft Corp. in order to pursue this goal). This proposal aims at studying the abelian and non-abelian fractional charges, and in particular to observe their peculiar statistics. While charges are preferably determined by measuring quantum shot noise, their statistics must be determined via interference experiments, where one particle goes around another. The experiments are very demanding since the even denominator fractions turn to be very fragile and thus can be observed only in the purest possible two dimensional electron gas and at the lowest temperatures. While until very recently such high quality samples were available only by a single grower (in the USA), we have the capability now to grow extremely pure samples with profound even denominator states. As will be detailed in the proposal, we have all the necessary tools to study charge and statistics of these fascinating excitations, due to our experience in crystal growth, shot noise and interferometry measurements.
Max ERC Funding
2 000 000 €
Duration
Start date: 2009-01-01, End date: 2013-12-31
Project acronym FRACTFRICT
Project Fracture and Friction: Rapid Dynamics of Material Failure
Researcher (PI) Jay Fineberg
Host Institution (HI) THE HEBREW UNIVERSITY OF JERUSALEM
Call Details Advanced Grant (AdG), PE3, ERC-2010-AdG_20100224
Summary FractFrict is a comprehensive study of the space-time dynamics that lead to the failure of both bulk materials and frictionally bound interfaces. In these systems, failure is precipitated by rapidly moving singular fields at the tips of propagating cracks or crack-like fronts that cause material damage at microscopic scales. These generate damage that is macroscopically reflected as characteristic large-scale, modes of material failure. Thus, the structure of the fields that microscopically drive failure is critically important for an overall understanding of how macroscopic failure occurs.
The innovative real-time measurements proposed here will provide fundamental understanding of the form of the singular fields, their modes of regularization and their relation to the resultant macroscopic modes of failure. Encompassing different classes of bulk materials and material interfaces.
We aim to:
[1] To establish a fundamental understanding of the dynamics of the near-tip singular fields, their regularization modes and how they couple to the macroscopic dynamics in both frictional motion and fracture.
[2] To determine the types of singular failure processes in different classes of materials and interfaces (e.g. the brittle to ductile transition in amorphous materials, the role of fast fracture processes in frictional motion).
[3] To establish local (microscopic) laws of friction/failure and how they evolve into their macroscopic counterparts
[4]. To identify the existence and origins of crack instabilities in bulk and interface failure
The insights obtained in this research will enable us to manipulate and/or predict material failure modes. The results of this study will shed considerable new light on fundamental open questions in fields as diverse as material design, tribology and geophysics.
Summary
FractFrict is a comprehensive study of the space-time dynamics that lead to the failure of both bulk materials and frictionally bound interfaces. In these systems, failure is precipitated by rapidly moving singular fields at the tips of propagating cracks or crack-like fronts that cause material damage at microscopic scales. These generate damage that is macroscopically reflected as characteristic large-scale, modes of material failure. Thus, the structure of the fields that microscopically drive failure is critically important for an overall understanding of how macroscopic failure occurs.
The innovative real-time measurements proposed here will provide fundamental understanding of the form of the singular fields, their modes of regularization and their relation to the resultant macroscopic modes of failure. Encompassing different classes of bulk materials and material interfaces.
We aim to:
[1] To establish a fundamental understanding of the dynamics of the near-tip singular fields, their regularization modes and how they couple to the macroscopic dynamics in both frictional motion and fracture.
[2] To determine the types of singular failure processes in different classes of materials and interfaces (e.g. the brittle to ductile transition in amorphous materials, the role of fast fracture processes in frictional motion).
[3] To establish local (microscopic) laws of friction/failure and how they evolve into their macroscopic counterparts
[4]. To identify the existence and origins of crack instabilities in bulk and interface failure
The insights obtained in this research will enable us to manipulate and/or predict material failure modes. The results of this study will shed considerable new light on fundamental open questions in fields as diverse as material design, tribology and geophysics.
Max ERC Funding
2 265 399 €
Duration
Start date: 2010-12-01, End date: 2016-11-30
Project acronym HQMAT
Project New Horizons in Quantum Matter: From Critical Fluids to High Temperature Superconductivity
Researcher (PI) Erez BERG
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary Understanding the low-temperature behavior of quantum correlated materials has long been one of the central challenges in condensed matter physics. Such materials exhibit a number of interesting phenomena, such as anomalous transport behavior, complex phase diagrams, and high-temperature superconductivity. However, their understanding has been hindered by the lack of suitable theoretical tools to handle such strongly interacting quantum ``liquids.''
Recent years have witnessed a wave of renewed interest in this long-standing, deep problem, both from condensed matter, high energy, and quantum information physicists. The goal of this research program is to exploit the recent progress on these problems to open new ways of understanding strongly-coupled unconventional quantum fluids. We will perform large-scale, sign problem-free QMC simulations of metals close to quantum critical points, focusing on new regimes beyond the traditional paradigms. New ways to diagnose transport from QMC data will be developed. Exotic phase transitions between an ordinary and a topologically-ordered, fractionalized metal will be studied. In addition, insights will be gained from analytical studies of strongly coupled lattice models, starting from the tractable limit of a large number of degrees of freedom per unit cell. The thermodynamic and transport properties of these models will be studied. These solvable examples will be used to provide a new window into the properties of strongly coupled quantum matter. We will seek ``organizing principles'' to describe such matter, such as emergent local quantum critical behavior and a hydrodynamic description of electron flow. Connections will be made with the ideas of universal bounds on transport and on the rate of spread of quantum information, as well as with insights from other techniques. While our study will mostly focus on generic, universal features of quantum fluids, implications for specific materials will also be studied.
Summary
Understanding the low-temperature behavior of quantum correlated materials has long been one of the central challenges in condensed matter physics. Such materials exhibit a number of interesting phenomena, such as anomalous transport behavior, complex phase diagrams, and high-temperature superconductivity. However, their understanding has been hindered by the lack of suitable theoretical tools to handle such strongly interacting quantum ``liquids.''
Recent years have witnessed a wave of renewed interest in this long-standing, deep problem, both from condensed matter, high energy, and quantum information physicists. The goal of this research program is to exploit the recent progress on these problems to open new ways of understanding strongly-coupled unconventional quantum fluids. We will perform large-scale, sign problem-free QMC simulations of metals close to quantum critical points, focusing on new regimes beyond the traditional paradigms. New ways to diagnose transport from QMC data will be developed. Exotic phase transitions between an ordinary and a topologically-ordered, fractionalized metal will be studied. In addition, insights will be gained from analytical studies of strongly coupled lattice models, starting from the tractable limit of a large number of degrees of freedom per unit cell. The thermodynamic and transport properties of these models will be studied. These solvable examples will be used to provide a new window into the properties of strongly coupled quantum matter. We will seek ``organizing principles'' to describe such matter, such as emergent local quantum critical behavior and a hydrodynamic description of electron flow. Connections will be made with the ideas of universal bounds on transport and on the rate of spread of quantum information, as well as with insights from other techniques. While our study will mostly focus on generic, universal features of quantum fluids, implications for specific materials will also be studied.
Max ERC Funding
1 515 400 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym HYBRIDQED
Project Hybrid Cavity Quantum Electrodynamics with Atoms and Circuits
Researcher (PI) Andreas Joachim Wallraff
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Starting Grant (StG), PE3, ERC-2009-StG
Summary We plan to investigate the strong coherent interaction of light and matter on the level of individual photons and atoms or atom-like systems. In particular, we will explore large dipole moment superconducting artificial atoms and natural Rydberg atoms interacting with radiation fields contained in quasi-one-dimensional on-chip microwave frequency resonators. In these resonators photons generate field strengths that exceed those in conventional mirror based resonators by orders of magnitude and they can also be stored for long times. This allows us to reach the strong coupling limit of cavity quantum electrodynamics (QED) using superconducting circuits, an approach known as circuit QED. In this project we will explore novel approaches to perform quantum optics experiments in circuits. We will develop techniques to generate and detect non-classical radiation fields using nonlinear resonators and chip-based interferometers. We will also further advance the circuit QED approach to quantum information processing. Our main goal is to develop an interface between circuit and atom based realizations of cavity QED. In particular, we will couple Rydberg atoms to on-chip resonators. To achieve this goal we will first investigate the interaction of ensembles of atoms in a beam with the coherent fields in a transmission line or a resonator. We will perform spectroscopy and we will investigate on-chip dispersive detection schemes for Rydberg atoms. We will also explore the interaction of Rydberg atoms with chip surfaces in dependence on materials, temperature and geometry. Experiments will be performed from 300 K down to millikelvin temperatures. We will realize and characterize on-chip traps for Rydberg atoms. Using trapped atoms we will explore their coherent dynamics. Finally, we aim at investigating the single atom and single photon limit. When realized, this system will be used to explore the first quantum coherent interface between atomic and solid state qubits.
Summary
We plan to investigate the strong coherent interaction of light and matter on the level of individual photons and atoms or atom-like systems. In particular, we will explore large dipole moment superconducting artificial atoms and natural Rydberg atoms interacting with radiation fields contained in quasi-one-dimensional on-chip microwave frequency resonators. In these resonators photons generate field strengths that exceed those in conventional mirror based resonators by orders of magnitude and they can also be stored for long times. This allows us to reach the strong coupling limit of cavity quantum electrodynamics (QED) using superconducting circuits, an approach known as circuit QED. In this project we will explore novel approaches to perform quantum optics experiments in circuits. We will develop techniques to generate and detect non-classical radiation fields using nonlinear resonators and chip-based interferometers. We will also further advance the circuit QED approach to quantum information processing. Our main goal is to develop an interface between circuit and atom based realizations of cavity QED. In particular, we will couple Rydberg atoms to on-chip resonators. To achieve this goal we will first investigate the interaction of ensembles of atoms in a beam with the coherent fields in a transmission line or a resonator. We will perform spectroscopy and we will investigate on-chip dispersive detection schemes for Rydberg atoms. We will also explore the interaction of Rydberg atoms with chip surfaces in dependence on materials, temperature and geometry. Experiments will be performed from 300 K down to millikelvin temperatures. We will realize and characterize on-chip traps for Rydberg atoms. Using trapped atoms we will explore their coherent dynamics. Finally, we aim at investigating the single atom and single photon limit. When realized, this system will be used to explore the first quantum coherent interface between atomic and solid state qubits.
Max ERC Funding
1 954 464 €
Duration
Start date: 2009-09-01, End date: 2014-08-31
Project acronym HydraMechanics
Project Mechanical Aspects of Hydra Morphogenesis
Researcher (PI) Kinneret Magda KEREN
Host Institution (HI) TECHNION - ISRAEL INSTITUTE OF TECHNOLOGY
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary Morphogenesis is one of the most remarkable examples of biological pattern formation. Despite substantial progress in the field, we still do not understand the organizational principles responsible for the robust convergence of the morphogenesis process, across scales, to form viable organisms under variable conditions. We focus here on the less-studied mechanical aspects of this problem, and aim to uncover how mechanical forces and feedback contribute to the formation and stabilization of the body plan. Regenerating Hydra offer a powerful platform to explore this direction, thanks to their simple body plan, extraordinary regeneration capabilities, and the accessibility and flexibility of their tissues. We propose to follow the regeneration of excised tissue segments, which inherit an aligned supra-cellular cytoskeletal organization from the parent Hydra, as well as cell aggregates, which lack any prior organization. We will employ advanced microscopy techniques and develop elaborate image analysis tools to track cytoskeletal organization and collective cell migration and correlate them with global tissue morphology, from the onset of regeneration all the way to the formation of complete animals. Furthermore, to directly probe the influence of mechanics on Hydra morphogenesis, we propose to apply various mechanical perturbations, and intervene with the axis formation process using external forces and mechanical constraints. Overall, the proposed work seeks to develop an effective phenomenological description of morphogenesis during Hydra regeneration, at the level of cells and tissues, and reveal the mechanical basis of this process. More generally, our research will shed light on the role of mechanics in animal morphogenesis, and inspire new approaches for using external forces to direct tissue engineering and advance regenerative medicine.
Summary
Morphogenesis is one of the most remarkable examples of biological pattern formation. Despite substantial progress in the field, we still do not understand the organizational principles responsible for the robust convergence of the morphogenesis process, across scales, to form viable organisms under variable conditions. We focus here on the less-studied mechanical aspects of this problem, and aim to uncover how mechanical forces and feedback contribute to the formation and stabilization of the body plan. Regenerating Hydra offer a powerful platform to explore this direction, thanks to their simple body plan, extraordinary regeneration capabilities, and the accessibility and flexibility of their tissues. We propose to follow the regeneration of excised tissue segments, which inherit an aligned supra-cellular cytoskeletal organization from the parent Hydra, as well as cell aggregates, which lack any prior organization. We will employ advanced microscopy techniques and develop elaborate image analysis tools to track cytoskeletal organization and collective cell migration and correlate them with global tissue morphology, from the onset of regeneration all the way to the formation of complete animals. Furthermore, to directly probe the influence of mechanics on Hydra morphogenesis, we propose to apply various mechanical perturbations, and intervene with the axis formation process using external forces and mechanical constraints. Overall, the proposed work seeks to develop an effective phenomenological description of morphogenesis during Hydra regeneration, at the level of cells and tissues, and reveal the mechanical basis of this process. More generally, our research will shed light on the role of mechanics in animal morphogenesis, and inspire new approaches for using external forces to direct tissue engineering and advance regenerative medicine.
Max ERC Funding
2 000 000 €
Duration
Start date: 2019-02-01, End date: 2024-01-31
Project acronym HyperQC
Project Hyper Quantum Criticality
Researcher (PI) Christian Rueegg
Host Institution (HI) PAUL SCHERRER INSTITUT
Call Details Consolidator Grant (CoG), PE3, ERC-2015-CoG
Summary Hyper Quantum Criticality – HyperQC is a major initiative with the aim of generating and controlling novel phases of correlated magnetic quantum matter, and of exploring them in high-precision experiments. A combination of new capabilities enabled by the development of instrumentation, pioneering ultra-fast studies and experiments on magnetic model materials will allow both the exploration of fundamental Hamiltonians and fully quantitative tests of quantum criticality in hyper-parameter space: temperature, magnetic field, pressure, energy, momentum and time.
HyperQC - Challenge. Direct control of the dimensionality, symmetry, chemical potential and interactions in magnetic materials is achieved by a new experimental set-up combining high magnetic fields and pressures with ultra-low temperatures, which will be installed on neutron scattering instruments at the Swiss Spallation Neutron Source SINQ. Experiments on a number of magnetic model materials allow the realization and high-precision measurements of the multi-dimensional quantum critical properties of systems including magnon Bose-Einstein Condensates, spin Luttinger liquids and renormalized classical ordered phases, as well as of other many-body phenomena in quantum spin systems.
HyperQC – Vision. Experiments on the time-dependent, non-equilibrium properties of quantum magnets and quantum critical points are new. Ultra-short laser and X-ray pulses are able to alter and measure the lattice, spin, orbital and electronic properties of solids, which has been demonstrated in recent experiments on multiferroic materials and superconductors. The effects of such pulses on a number of well-characterized model quantum magnets will be investigated with the aim of studying the time-dependent dynamics of quantum critical systems for the first time.
Summary
Hyper Quantum Criticality – HyperQC is a major initiative with the aim of generating and controlling novel phases of correlated magnetic quantum matter, and of exploring them in high-precision experiments. A combination of new capabilities enabled by the development of instrumentation, pioneering ultra-fast studies and experiments on magnetic model materials will allow both the exploration of fundamental Hamiltonians and fully quantitative tests of quantum criticality in hyper-parameter space: temperature, magnetic field, pressure, energy, momentum and time.
HyperQC - Challenge. Direct control of the dimensionality, symmetry, chemical potential and interactions in magnetic materials is achieved by a new experimental set-up combining high magnetic fields and pressures with ultra-low temperatures, which will be installed on neutron scattering instruments at the Swiss Spallation Neutron Source SINQ. Experiments on a number of magnetic model materials allow the realization and high-precision measurements of the multi-dimensional quantum critical properties of systems including magnon Bose-Einstein Condensates, spin Luttinger liquids and renormalized classical ordered phases, as well as of other many-body phenomena in quantum spin systems.
HyperQC – Vision. Experiments on the time-dependent, non-equilibrium properties of quantum magnets and quantum critical points are new. Ultra-short laser and X-ray pulses are able to alter and measure the lattice, spin, orbital and electronic properties of solids, which has been demonstrated in recent experiments on multiferroic materials and superconductors. The effects of such pulses on a number of well-characterized model quantum magnets will be investigated with the aim of studying the time-dependent dynamics of quantum critical systems for the first time.
Max ERC Funding
2 328 649 €
Duration
Start date: 2016-12-01, End date: 2021-11-30
Project acronym IMAGINE
Project Non-Invasive Imaging of Nanoscale Electronic Transport
Researcher (PI) Christian Lukas Degen
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary Electronic transport in nanostructures and thin films shows a rich variety of physical effects that have been fundamental to the development of modern electronics and communication devices. The standard method for investigating electronic transport – resistance measurements – does not provide any information on the nanoscale current distribution in such structures. The lack of spatial information is unfortunate, because the current distribution plays a key role in many intriguing physical phenomena. Having a technique at hand that could simply look at nanoscale current flow would be immensely valuable.
In this project we propose to exploit sensitive magnetic microscopy to directly access the current distribution in nanostructures with ~15nm spatial resolution. Our approach is based on the recent technique of scanning diamond magnetometry (SDM), a scanned-probe method that utilizes a single spin in a diamond tip as a high-resolution sensor of magnetic field. Conceived in 2008 by the PI, SDM exploits quantum metrology to achieve very high sensitivities, and has recently enabled a breakthrough in the passive analysis of magnetic surfaces. Our proposal has three objectives: (i) Lay the instrumental and conceptual groundwork required for imaging tiny (<10nA) current variations in two-dimensional conductors. (ii) Demonstrate imaging of a variety of mesoscopic transport features on a well-established model system: Mono- and bilayer graphene. (iii) Explore the potential of our technique for probing electronic properties beyond transport, like phase transitions and photoexcitation.
Together, our experiments are designed to establish a powerful new technology for imaging current distributions non-invasively and with nanometer spatial resolution. This capability will provide the unique opportunity for directly looking at electronic transport in nanostructures, with a potentially transformative impact on condensed matter physics, materials science and electrical engineering.
Summary
Electronic transport in nanostructures and thin films shows a rich variety of physical effects that have been fundamental to the development of modern electronics and communication devices. The standard method for investigating electronic transport – resistance measurements – does not provide any information on the nanoscale current distribution in such structures. The lack of spatial information is unfortunate, because the current distribution plays a key role in many intriguing physical phenomena. Having a technique at hand that could simply look at nanoscale current flow would be immensely valuable.
In this project we propose to exploit sensitive magnetic microscopy to directly access the current distribution in nanostructures with ~15nm spatial resolution. Our approach is based on the recent technique of scanning diamond magnetometry (SDM), a scanned-probe method that utilizes a single spin in a diamond tip as a high-resolution sensor of magnetic field. Conceived in 2008 by the PI, SDM exploits quantum metrology to achieve very high sensitivities, and has recently enabled a breakthrough in the passive analysis of magnetic surfaces. Our proposal has three objectives: (i) Lay the instrumental and conceptual groundwork required for imaging tiny (<10nA) current variations in two-dimensional conductors. (ii) Demonstrate imaging of a variety of mesoscopic transport features on a well-established model system: Mono- and bilayer graphene. (iii) Explore the potential of our technique for probing electronic properties beyond transport, like phase transitions and photoexcitation.
Together, our experiments are designed to establish a powerful new technology for imaging current distributions non-invasively and with nanometer spatial resolution. This capability will provide the unique opportunity for directly looking at electronic transport in nanostructures, with a potentially transformative impact on condensed matter physics, materials science and electrical engineering.
Max ERC Funding
2 491 490 €
Duration
Start date: 2019-10-01, End date: 2024-09-30
Project acronym InCell
Project High speed AFM imaging of molecular processes inside living cells
Researcher (PI) Georg FANTNER
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Consolidator Grant (CoG), PE3, ERC-2017-COG
Summary Imaging the inside of living cells with single nanometre resolution has been a long-standing dream in bio-microscopy. Direct observation of changes to molecular networks inside of living cells would revolutionize the way we study structural cell biology. Unfortunately, no such tool exists. Atomic force microscopy (AFM) is the closest we have, to nanoscale functional imaging of cells in their native, fluid environment. However, it is limited to imaging the outside of the cell.
With InCell, I will remedy this by developing an AFM capable of imaging the inside of living cells. The approach is based on a microfabricated high speed AFM cantilever encased in a double barrel patch-clamp shell. The patch clamp shell seals onto the plasma membrane of the cell, so that the tip of the AFM cantilever can enter the cell without causing the cytosol to leak out. Parasitic interactions of the AFM tip with the cytosol will be subtracted from the cantilever deflection signal, using high speed photo-thermal off-resonance tapping (PT-ORT), a novel AFM mode we have recently developed in my lab. This allows the extraction of the true tip-sample interaction, even in viscous fluids. A dedicated InCell HS-AFM combined with confocal optical microscopy will be used to guide the InCell cantilever inside the cell to the area of interest.
Using this minimally invasive technique we will study the formation of clathrin coated pits, a crucial part of endocytosis. By imaging for the first time the nanoscale dynamics of this process in living cells, we aim to answer fundamental questions about the clathrin coat assembly. We will characterize the kinetics, stability and force generation by the clathrin lattice. This will be the first example of how enabling nanoscale imaging inside living cells will be a game changer in cell biology. It will open up a myriad of possibilities for the study of vesicular transport, viral and bacterial infection, nuclear pore transport, cell signalling and many more.
Summary
Imaging the inside of living cells with single nanometre resolution has been a long-standing dream in bio-microscopy. Direct observation of changes to molecular networks inside of living cells would revolutionize the way we study structural cell biology. Unfortunately, no such tool exists. Atomic force microscopy (AFM) is the closest we have, to nanoscale functional imaging of cells in their native, fluid environment. However, it is limited to imaging the outside of the cell.
With InCell, I will remedy this by developing an AFM capable of imaging the inside of living cells. The approach is based on a microfabricated high speed AFM cantilever encased in a double barrel patch-clamp shell. The patch clamp shell seals onto the plasma membrane of the cell, so that the tip of the AFM cantilever can enter the cell without causing the cytosol to leak out. Parasitic interactions of the AFM tip with the cytosol will be subtracted from the cantilever deflection signal, using high speed photo-thermal off-resonance tapping (PT-ORT), a novel AFM mode we have recently developed in my lab. This allows the extraction of the true tip-sample interaction, even in viscous fluids. A dedicated InCell HS-AFM combined with confocal optical microscopy will be used to guide the InCell cantilever inside the cell to the area of interest.
Using this minimally invasive technique we will study the formation of clathrin coated pits, a crucial part of endocytosis. By imaging for the first time the nanoscale dynamics of this process in living cells, we aim to answer fundamental questions about the clathrin coat assembly. We will characterize the kinetics, stability and force generation by the clathrin lattice. This will be the first example of how enabling nanoscale imaging inside living cells will be a game changer in cell biology. It will open up a myriad of possibilities for the study of vesicular transport, viral and bacterial infection, nuclear pore transport, cell signalling and many more.
Max ERC Funding
1 999 925 €
Duration
Start date: 2018-04-01, End date: 2023-03-31
Project acronym INSEETO
Project In-situ second harmonic generation for emergent electronics in transition-metal oxides
Researcher (PI) Manfred FIEBIG
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2015-AdG
Summary Since transition-metal oxides heterostructures can be grown by pulsed laser deposition (PLD) with semiconductor-like accuracy, fascinating phases and functionalities derived from their spin-charge correlations have been discovered. So far, reflection high-energy electron diffraction is the only widely established technique for monitoring the structure and homogeneity of multilayers in-situ, while they are growing, and provide direct feedback information on how to optimise the growth process. With our proposal we will introduce second harmonic generation (SHG) as new in-situ technique that allows us to track spin-and charge-related phenomena such as ferroelectricity, (anti-) ferromagnetism, insulator-metal transitions, domain coupling effects or interface states in a non-invasive way throughout the deposition process. With this we are pursuing two goals: first, to establish SHG as new in-situ characterization technique in PLD which monitors strong spin-charge correlation effects while they emerge during growth; second, to apply in-situ SHG for tailoring novel functionalities in exemplary chosen types of transition-metal-oxide heterostructures of great current interest. These model systems are (i) proper ferroelectrics tuned to high-k dielectric response and improper ferroelectrics whose behaviour is determined by the unusual nature of the polar state; (ii) compounds in which the interplay of strain and defects leads to novel and reversibly tuneable states of matter; (iii) heterostructures with functionalities originating from the interaction across interfaces. In-situ SHG as new, property-monitoring tool in PLD has an immense potential to uncover new states of matter and functionalities. We are convinced that this will play an essential role in the leap towards the next generation of functional oxide heterostructures.
Summary
Since transition-metal oxides heterostructures can be grown by pulsed laser deposition (PLD) with semiconductor-like accuracy, fascinating phases and functionalities derived from their spin-charge correlations have been discovered. So far, reflection high-energy electron diffraction is the only widely established technique for monitoring the structure and homogeneity of multilayers in-situ, while they are growing, and provide direct feedback information on how to optimise the growth process. With our proposal we will introduce second harmonic generation (SHG) as new in-situ technique that allows us to track spin-and charge-related phenomena such as ferroelectricity, (anti-) ferromagnetism, insulator-metal transitions, domain coupling effects or interface states in a non-invasive way throughout the deposition process. With this we are pursuing two goals: first, to establish SHG as new in-situ characterization technique in PLD which monitors strong spin-charge correlation effects while they emerge during growth; second, to apply in-situ SHG for tailoring novel functionalities in exemplary chosen types of transition-metal-oxide heterostructures of great current interest. These model systems are (i) proper ferroelectrics tuned to high-k dielectric response and improper ferroelectrics whose behaviour is determined by the unusual nature of the polar state; (ii) compounds in which the interplay of strain and defects leads to novel and reversibly tuneable states of matter; (iii) heterostructures with functionalities originating from the interaction across interfaces. In-situ SHG as new, property-monitoring tool in PLD has an immense potential to uncover new states of matter and functionalities. We are convinced that this will play an essential role in the leap towards the next generation of functional oxide heterostructures.
Max ERC Funding
2 498 714 €
Duration
Start date: 2017-01-01, End date: 2021-12-31
Project acronym ISCQuM
Project Imaging, Spectroscopy and Control of Quantum states in advanced Materials
Researcher (PI) Fabrizio CARBONE
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Consolidator Grant (CoG), PE3, ERC-2017-COG
Summary Atomic confinement in 2D materials, topological protection in strong spin-orbit coupling systems or chiral magnets, all result in spin/charge textured states of matter. For example skyrmions, a whirling distribution of spins, behave as individual particles which controlled creation/annihilation/motion is of great importance in spintronics. To achieve control over skyrmions, or more generally over the constituents of disordered elastic media (vortices in superconductors, domain walls in magnets to name a few), the fundamental interplay between short-range and long-range interactions, influenced by topological protection, disorder and confinement, has to be understood and manipulated. This project aims at controlling with electromagnetic pulses a handful of charges and spins in nanostructured materials to be filmed with nm/fs resolution by time-resolved Transmission Electron Microscopy. I propose to image and shape confined electromagnetic fields (plasmons) in nanostructured novel materials. With this ability, we will implement/demonstrate the ultrafast writing and erasing of individual skyrmions in topological magnets. These experiments will enable the fundamental investigation of defects in topological networks and possibly seed new ideas for application in ultradense and ultrafast data storage devices. Similarly, pinning of vortices in type II superconductors will be controlled by light and imaged, gaining new insights into out of equilibrium superconductivity. In my laboratory, shaping and filming plasmonic fields down to the nm-fs scales have been demonstrated, as well as laser-writing and imaging skyrmions in nanostructures. ISCQuM will allow implementing crucial advances: i) extending our photoexcitation to the far-infrared for creating few-cycles electromagnetic pulses and exciting structural or electronic collective modes; ii) upgrading our detection to higher sensitivity and spatial resolution, extending our ability to image spin and charge distributions.
Summary
Atomic confinement in 2D materials, topological protection in strong spin-orbit coupling systems or chiral magnets, all result in spin/charge textured states of matter. For example skyrmions, a whirling distribution of spins, behave as individual particles which controlled creation/annihilation/motion is of great importance in spintronics. To achieve control over skyrmions, or more generally over the constituents of disordered elastic media (vortices in superconductors, domain walls in magnets to name a few), the fundamental interplay between short-range and long-range interactions, influenced by topological protection, disorder and confinement, has to be understood and manipulated. This project aims at controlling with electromagnetic pulses a handful of charges and spins in nanostructured materials to be filmed with nm/fs resolution by time-resolved Transmission Electron Microscopy. I propose to image and shape confined electromagnetic fields (plasmons) in nanostructured novel materials. With this ability, we will implement/demonstrate the ultrafast writing and erasing of individual skyrmions in topological magnets. These experiments will enable the fundamental investigation of defects in topological networks and possibly seed new ideas for application in ultradense and ultrafast data storage devices. Similarly, pinning of vortices in type II superconductors will be controlled by light and imaged, gaining new insights into out of equilibrium superconductivity. In my laboratory, shaping and filming plasmonic fields down to the nm-fs scales have been demonstrated, as well as laser-writing and imaging skyrmions in nanostructures. ISCQuM will allow implementing crucial advances: i) extending our photoexcitation to the far-infrared for creating few-cycles electromagnetic pulses and exciting structural or electronic collective modes; ii) upgrading our detection to higher sensitivity and spatial resolution, extending our ability to image spin and charge distributions.
Max ERC Funding
1 994 385 €
Duration
Start date: 2019-03-01, End date: 2024-02-29
Project acronym LASER-ARPES
Project Laser based photoemission: revolutionizing the spectroscopy of correlated electrons
Researcher (PI) Felix Baumberger
Host Institution (HI) UNIVERSITE DE GENEVE
Call Details Starting Grant (StG), PE3, ERC-2007-StG
Summary It is proposed to develop a novel instrument for angular resolved photoelectron spectroscopy (ARPES) by combining a laser based ultraviolet light source with a state-of-the-art electron spectrometer. This combination will be unique in Europe and will push this important technique to an entirely new level of resolution, comparable to the thermal broadening at 1 K and nearly an order of magnitude lower than the resolution achievable in practical ARPES experiments with the latest synchrotron light sources. The low photon energy of this new source will also markedly enhance the bulk sensitivity of ARPES and thus enable the investigation of interesting materials that were not accessible so far. These new capabilities will be used to study the subtle quantum many-body states of correlated electrons in transition metal oxides, a frontier topic in condensed-matter physics. Specifically, we will focus on electronic instabilities in perovskites and elucidate how different degrees of freedom play together to determine the often vastly different properties of chemically closely related materials. Moreover, we will apply modern electron spectroscopy to correlated molecular solids with complex phase diagrams that challenge existing theory for satisfactory explanations. This field is largely unexplored but is fundamental for advances in molecular electronics.
Summary
It is proposed to develop a novel instrument for angular resolved photoelectron spectroscopy (ARPES) by combining a laser based ultraviolet light source with a state-of-the-art electron spectrometer. This combination will be unique in Europe and will push this important technique to an entirely new level of resolution, comparable to the thermal broadening at 1 K and nearly an order of magnitude lower than the resolution achievable in practical ARPES experiments with the latest synchrotron light sources. The low photon energy of this new source will also markedly enhance the bulk sensitivity of ARPES and thus enable the investigation of interesting materials that were not accessible so far. These new capabilities will be used to study the subtle quantum many-body states of correlated electrons in transition metal oxides, a frontier topic in condensed-matter physics. Specifically, we will focus on electronic instabilities in perovskites and elucidate how different degrees of freedom play together to determine the often vastly different properties of chemically closely related materials. Moreover, we will apply modern electron spectroscopy to correlated molecular solids with complex phase diagrams that challenge existing theory for satisfactory explanations. This field is largely unexplored but is fundamental for advances in molecular electronics.
Max ERC Funding
1 450 825 €
Duration
Start date: 2008-08-01, End date: 2013-07-31
Project acronym LEGOTOP
Project From Local Elements to Globally Ordered TOPological states of matter
Researcher (PI) Yuval OREG
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2017-ADG
Summary We present a novel constructive approach for realizations of topological states of matter. Our approach starts with well-understood building blocks, and proceeds towards coupling them to create the desired states. This approach promises both a guide for a tunable experimental realization of states which have not been observed so far, and a theoretical tool for deeper understanding of different topological states, their dualities and inter-relations.
We will apply the constructive approach in two different directions. In the first direction our goal will be the construction of topological superconductors. Our tool will be Josephson junctions in which superconductors are coupled by two- and three-dimensional electronic non-superconducting systems. Two dimensional examples include transition metal dichalcogenides, Quantum Hall states, Quantum Anomalous Hall states, and the (111) bi-layer state, which may be viewed as a fractionalized electron-hole condensate. Three dimensional examples include Weyl semi-metals and weak topological insulators.
In the second direction our goal is the construction of fractionalized spin liquid states. Our building block will be a Majorana-Cooper box, which is a superconducting quantum dot coupled to semi-conducting wires that host Majorana zero modes. We will consider arrays of such boxes. The ratio of the box's charging energy to inter-box tunnel-coupling determines whether the array is superconducting or insulating. We will aim to use insulating arrays for realizing fractionalized and non-abelian spin liquids, study the transition to the superconducting state, and search for possible relations between the topological properties on both sides of the transition.
A deeper comprehension and a feasible path for realization of these states would have a profound effect on the field of topological matter and will open novel avenues for universal topological quantum computers.
Summary
We present a novel constructive approach for realizations of topological states of matter. Our approach starts with well-understood building blocks, and proceeds towards coupling them to create the desired states. This approach promises both a guide for a tunable experimental realization of states which have not been observed so far, and a theoretical tool for deeper understanding of different topological states, their dualities and inter-relations.
We will apply the constructive approach in two different directions. In the first direction our goal will be the construction of topological superconductors. Our tool will be Josephson junctions in which superconductors are coupled by two- and three-dimensional electronic non-superconducting systems. Two dimensional examples include transition metal dichalcogenides, Quantum Hall states, Quantum Anomalous Hall states, and the (111) bi-layer state, which may be viewed as a fractionalized electron-hole condensate. Three dimensional examples include Weyl semi-metals and weak topological insulators.
In the second direction our goal is the construction of fractionalized spin liquid states. Our building block will be a Majorana-Cooper box, which is a superconducting quantum dot coupled to semi-conducting wires that host Majorana zero modes. We will consider arrays of such boxes. The ratio of the box's charging energy to inter-box tunnel-coupling determines whether the array is superconducting or insulating. We will aim to use insulating arrays for realizing fractionalized and non-abelian spin liquids, study the transition to the superconducting state, and search for possible relations between the topological properties on both sides of the transition.
A deeper comprehension and a feasible path for realization of these states would have a profound effect on the field of topological matter and will open novel avenues for universal topological quantum computers.
Max ERC Funding
1 532 163 €
Duration
Start date: 2018-10-01, End date: 2023-09-30
Project acronym MEGA-XUV
Project Efficient megahertz coherent XUV light source
Researcher (PI) Thomas Südmeyer
Host Institution (HI) UNIVERSITE DE NEUCHATEL
Call Details Starting Grant (StG), PE3, ERC-2011-StG_20101014
Summary "Coherent extreme ultraviolet (XUV) light sources open up new opportunities for science and technology. Promising examples are attosecond metrology, spectroscopic and structural analysis of matter on a nanometer scale, high resolution XUV-microscopy and lithography. The most promising technique for table-top sources is femtosecond laser-driven high-harmonic generation (HHG) in gases. Unfortunately, their XUV photon flux is not sufficient for most applications. This is caused by the low average power of the kHz repetition rate driving lasers (<10 W) and the poor conversion efficiency (<10-6). Following the traditional path of increasing the power, numerous research teams are engineering larger and more complex femtosecond high-power amplifier systems, which are supposed to provide several kilowatts of average power in the next decade. However, it is questionable if such systems can easily serve as tool for further scientific studies with XUV light.
The goal of this proposal is the realization of a simpler and more efficient source of high-flux XUV radiation. Instead of amplifying a laser beam to several kW of power and dumping it after the HHG interaction, the generation of high harmonics is placed directly inside the intra-cavity multi-kilowatt beam of a femtosecond laser. Thus, the unconverted light is “recycled”, and the laser medium only needs to compensate for the low losses of the resonator. Achieving passive femtosecond pulse formation at these record-high power levels will require eliminating any destabilizing effects inside the resonator. This appears to be only feasible with ultrafast thin disk lasers, because all key components are used in reflection.
Exploiting the scientific opportunities of the resulting table-top multi-MHz coherent XUV light source in various interdisciplinary applications is the second major part of this project. The developed XUV source will be transportable, which will enable the fast implementation of joint measurements."
Summary
"Coherent extreme ultraviolet (XUV) light sources open up new opportunities for science and technology. Promising examples are attosecond metrology, spectroscopic and structural analysis of matter on a nanometer scale, high resolution XUV-microscopy and lithography. The most promising technique for table-top sources is femtosecond laser-driven high-harmonic generation (HHG) in gases. Unfortunately, their XUV photon flux is not sufficient for most applications. This is caused by the low average power of the kHz repetition rate driving lasers (<10 W) and the poor conversion efficiency (<10-6). Following the traditional path of increasing the power, numerous research teams are engineering larger and more complex femtosecond high-power amplifier systems, which are supposed to provide several kilowatts of average power in the next decade. However, it is questionable if such systems can easily serve as tool for further scientific studies with XUV light.
The goal of this proposal is the realization of a simpler and more efficient source of high-flux XUV radiation. Instead of amplifying a laser beam to several kW of power and dumping it after the HHG interaction, the generation of high harmonics is placed directly inside the intra-cavity multi-kilowatt beam of a femtosecond laser. Thus, the unconverted light is “recycled”, and the laser medium only needs to compensate for the low losses of the resonator. Achieving passive femtosecond pulse formation at these record-high power levels will require eliminating any destabilizing effects inside the resonator. This appears to be only feasible with ultrafast thin disk lasers, because all key components are used in reflection.
Exploiting the scientific opportunities of the resulting table-top multi-MHz coherent XUV light source in various interdisciplinary applications is the second major part of this project. The developed XUV source will be transportable, which will enable the fast implementation of joint measurements."
Max ERC Funding
1 500 000 €
Duration
Start date: 2012-03-01, End date: 2017-02-28
Project acronym MiTopMat
Project Microstructured Topological Materials: A novel route towards topological electronics
Researcher (PI) Philip MOLL
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Starting Grant (StG), PE3, ERC-2016-STG
Summary Topological semi-metals such as Cd3As2 or TaAs are characterized by two bands crossing at isolated points in momentum space and a linear electronic dispersion around these crossing points. This linear dispersion can be mapped onto the Dirac- or Weyl-Hamiltonian, describing relativistic massless fermions, and thus relativistic phenomena from high-energy physics may appear in these materials. For example, the chirality, χ=±1, is a conserved quantity for massless fermions, separating the electrons into two distinct chiral species. A new class of topological electronics has been proposed based on chirality imbalance and chiral currents taking the role of charge imbalance and charge currents in electronics. Such devices promise technological advances in speed, energy efficiency, and quantum coherent processes at elevated temperatures.
We will research the basic physical phenomena on which topological electronics is based: 1) The ability to interact electrically with the chiral states in a topological semi-metal is an essential prerequisite for their application. We will investigate whether currents in the Fermi arc surface states can be induced by charge currents and selectively detected by voltage measurements. 2) Weyl materials are more robust against defects and therefore of interest for industrial fabrication. We will experimentally test this topological protection in high-field transport experiments in a wide range of Weyl materials. 3) Recently, topological processes leading to fast, tuneable and efficient voltage inversion were predicted. We will investigate the phenomenon, fabricate and characterize such inverters, and assess their performance. MiTopMat thus aims to build the first prototype of a topological voltage inverter.
These goals are challenging but achievable: MiTopMat’s research plan is based on Focused Ion Beam microfabrication, which we have successfully shown to be a promising route to fabricate chiral devices.
Summary
Topological semi-metals such as Cd3As2 or TaAs are characterized by two bands crossing at isolated points in momentum space and a linear electronic dispersion around these crossing points. This linear dispersion can be mapped onto the Dirac- or Weyl-Hamiltonian, describing relativistic massless fermions, and thus relativistic phenomena from high-energy physics may appear in these materials. For example, the chirality, χ=±1, is a conserved quantity for massless fermions, separating the electrons into two distinct chiral species. A new class of topological electronics has been proposed based on chirality imbalance and chiral currents taking the role of charge imbalance and charge currents in electronics. Such devices promise technological advances in speed, energy efficiency, and quantum coherent processes at elevated temperatures.
We will research the basic physical phenomena on which topological electronics is based: 1) The ability to interact electrically with the chiral states in a topological semi-metal is an essential prerequisite for their application. We will investigate whether currents in the Fermi arc surface states can be induced by charge currents and selectively detected by voltage measurements. 2) Weyl materials are more robust against defects and therefore of interest for industrial fabrication. We will experimentally test this topological protection in high-field transport experiments in a wide range of Weyl materials. 3) Recently, topological processes leading to fast, tuneable and efficient voltage inversion were predicted. We will investigate the phenomenon, fabricate and characterize such inverters, and assess their performance. MiTopMat thus aims to build the first prototype of a topological voltage inverter.
These goals are challenging but achievable: MiTopMat’s research plan is based on Focused Ion Beam microfabrication, which we have successfully shown to be a promising route to fabricate chiral devices.
Max ERC Funding
1 836 070 €
Duration
Start date: 2017-12-01, End date: 2022-11-30
Project acronym MODMAT
Project Nonequilibrium dynamical mean-field theory: From models to materials
Researcher (PI) Philipp WERNER
Host Institution (HI) UNIVERSITE DE FRIBOURG
Call Details Consolidator Grant (CoG), PE3, ERC-2016-COG
Summary Pump-probe techniques are a powerful experimental tool for the study of strongly correlated electron systems. The strategy is to drive a material out of its equilibrium state by a laser pulse, and to measure the subsequent dynamics on the intrinsic timescale of the electron, spin and lattice degrees of freedom. This allows to disentangle competing low-energy processes along the time axis and to gain new insights into correlation phenomena. Pump-probe experiments have also shown that external stimulation can induce novel transient states, which raises the exciting prospect of nonequilibrium control of material properties.
The ab-initio simulation of correlated materials is challenging, and the prediction of a material's behavior under nonequilibrium conditions is an even more ambitious task. In the equilibrium context, a significant recent advance is the implementation of dynamical mean field theory (DMFT) schemes capable of treating dynamically screened interactions. These techniques have enabled the combination of the GW ab-initio method and DMFT in realistic contexts. Another recent development is the nonequilibrium extension of DMFT, which has been established as a flexible tool for the simulation of time-dependent phenomena in correlated lattice systems.
The goal of this research project is to combine these two recently developed computational techniques into a GW and nonequilibrium DMFT based ab-initio framework capable of delivering quantitative and material-specific predictions of the nonequilibrium properties of correlated compounds. The new formalism will be used to study photoinduced phasetransitions, unconventional superconductors with driven phonons, and strongly correlated devices such as Mott insulating solar cells.
Summary
Pump-probe techniques are a powerful experimental tool for the study of strongly correlated electron systems. The strategy is to drive a material out of its equilibrium state by a laser pulse, and to measure the subsequent dynamics on the intrinsic timescale of the electron, spin and lattice degrees of freedom. This allows to disentangle competing low-energy processes along the time axis and to gain new insights into correlation phenomena. Pump-probe experiments have also shown that external stimulation can induce novel transient states, which raises the exciting prospect of nonequilibrium control of material properties.
The ab-initio simulation of correlated materials is challenging, and the prediction of a material's behavior under nonequilibrium conditions is an even more ambitious task. In the equilibrium context, a significant recent advance is the implementation of dynamical mean field theory (DMFT) schemes capable of treating dynamically screened interactions. These techniques have enabled the combination of the GW ab-initio method and DMFT in realistic contexts. Another recent development is the nonequilibrium extension of DMFT, which has been established as a flexible tool for the simulation of time-dependent phenomena in correlated lattice systems.
The goal of this research project is to combine these two recently developed computational techniques into a GW and nonequilibrium DMFT based ab-initio framework capable of delivering quantitative and material-specific predictions of the nonequilibrium properties of correlated compounds. The new formalism will be used to study photoinduced phasetransitions, unconventional superconductors with driven phonons, and strongly correlated devices such as Mott insulating solar cells.
Max ERC Funding
1 854 321 €
Duration
Start date: 2017-05-01, End date: 2022-04-30
Project acronym MUNATOP
Project Multi-Dimensional Study of non Abelian Topological States of Matter
Researcher (PI) Adiel (Ady) Stern
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary Non-abelian topological states of matter are of great interest in condensed matter physics,
both due to their extraordinary fundamental properties and to their possible use for quantum
computation. The insensitivity of their topological characteristics to disorder, noise,
and interaction with the environment may lead to realization of quantum computers with
very long coherence times. The realization of a quantum computer ranks among the foremost
outstanding problems in physics, particularly in light of the revolutionary rewards
the achievement of this goal promises.
The proposed theoretical study is multi-dimensional. On the methodological side the
multi-dimensionality is in the breadth of the studies we discuss, ranging all the way from
phenomenology to mathematical physics. We will aim at detailed understanding of present
and future experimental results. We will analyze experimental setups designed to identify,
characterize and manipulate non-abelian states. And we will propose and classify novel
non-abelian states. On the concrete side, the multi-dimensionality is literal. The systems
we consider include quantum dots, one dimensional quantum wires, two dimensional planar
systems, and surfaces of three dimensional systems.
Our proposal starts with Majorana fermions in systems where spin-orbit coupling, Zeeman
fields and proximity coupling to superconductivity are at play. It continues with “edge
anyons”, non-abelian quasiparticles residing on edges of abelian Quantum Hall states. It
ends with open issues in the physics of the Quantum Hall Effect.
We expect that this study will result in clear schemes for unquestionable experimental
identification of Majorana fermions, new predictions for more of their measurable consequences,
understanding of the feasibility of fractionalized phases in quantum wires, feasible
experimental schemes for realizing and observing edge anyons, steps towards their classification,
and better understanding of quantum Hall interferometry.
Summary
Non-abelian topological states of matter are of great interest in condensed matter physics,
both due to their extraordinary fundamental properties and to their possible use for quantum
computation. The insensitivity of their topological characteristics to disorder, noise,
and interaction with the environment may lead to realization of quantum computers with
very long coherence times. The realization of a quantum computer ranks among the foremost
outstanding problems in physics, particularly in light of the revolutionary rewards
the achievement of this goal promises.
The proposed theoretical study is multi-dimensional. On the methodological side the
multi-dimensionality is in the breadth of the studies we discuss, ranging all the way from
phenomenology to mathematical physics. We will aim at detailed understanding of present
and future experimental results. We will analyze experimental setups designed to identify,
characterize and manipulate non-abelian states. And we will propose and classify novel
non-abelian states. On the concrete side, the multi-dimensionality is literal. The systems
we consider include quantum dots, one dimensional quantum wires, two dimensional planar
systems, and surfaces of three dimensional systems.
Our proposal starts with Majorana fermions in systems where spin-orbit coupling, Zeeman
fields and proximity coupling to superconductivity are at play. It continues with “edge
anyons”, non-abelian quasiparticles residing on edges of abelian Quantum Hall states. It
ends with open issues in the physics of the Quantum Hall Effect.
We expect that this study will result in clear schemes for unquestionable experimental
identification of Majorana fermions, new predictions for more of their measurable consequences,
understanding of the feasibility of fractionalized phases in quantum wires, feasible
experimental schemes for realizing and observing edge anyons, steps towards their classification,
and better understanding of quantum Hall interferometry.
Max ERC Funding
1 529 107 €
Duration
Start date: 2013-10-01, End date: 2018-09-30
Project acronym MUSiC
Project Quantum Metamaterials in the Ultra Strong Coupling regime
Researcher (PI) Jérôme Jean-Constant Faist
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary Due to their mixed photon-electronic excitation character, cavity polaritons have highly interesting properties. Especially interesting is the so-called ultrastrong coupling regime, reached when the strength of the photon-two-level system coupling is larger than the energy of the resonant state. We have recently demonstrated that terahertz metamaterials coupled to high-mobility two-dimensional electron gases is an almost ideal, field-tunable system that enables the exploration of this ultra-strong coupling regime.
In this project, we want to explore four key physical questions opened by this new approach. First we plan to explore the limit of ultra-strong coupling in our systems, including the emission of Casimir-like squeezed vacuum photons upon non-adiabatic change in the coupling energy and parametric generation of light. Secondly we would like to test a theoretical prediction anticipating, in the ultra-strong coupling regime, a quantum phase transition to a Dicke superradiant state upon substitution of the GaAs/AlGaAs two-dimensional electron gas by a graphene layer or multilayers. Thirdly, we claim that our metamaterial-based system also enables the study of coupled polaritons by either direct meta-atom electromagnetic coupling or using a waveguide bus and superconducting circuits. Finally, we want to explore polaritonic emitters and non-linear elements.
Summary
Due to their mixed photon-electronic excitation character, cavity polaritons have highly interesting properties. Especially interesting is the so-called ultrastrong coupling regime, reached when the strength of the photon-two-level system coupling is larger than the energy of the resonant state. We have recently demonstrated that terahertz metamaterials coupled to high-mobility two-dimensional electron gases is an almost ideal, field-tunable system that enables the exploration of this ultra-strong coupling regime.
In this project, we want to explore four key physical questions opened by this new approach. First we plan to explore the limit of ultra-strong coupling in our systems, including the emission of Casimir-like squeezed vacuum photons upon non-adiabatic change in the coupling energy and parametric generation of light. Secondly we would like to test a theoretical prediction anticipating, in the ultra-strong coupling regime, a quantum phase transition to a Dicke superradiant state upon substitution of the GaAs/AlGaAs two-dimensional electron gas by a graphene layer or multilayers. Thirdly, we claim that our metamaterial-based system also enables the study of coupled polaritons by either direct meta-atom electromagnetic coupling or using a waveguide bus and superconducting circuits. Finally, we want to explore polaritonic emitters and non-linear elements.
Max ERC Funding
2 496 560 €
Duration
Start date: 2014-04-01, End date: 2019-03-31
Project acronym NaMic
Project Nanowire Atomic Force Microscopy for Real Time Imaging of Nanoscale Biological Processes
Researcher (PI) Georg Ernest Fantner
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Starting Grant (StG), PE3, ERC-2012-StG_20111012
Summary Short summary:
The ability to measure structures with nanoscale resolution continues to transform physics, materials science and life science alike. Nevertheless, while there are excellent tools to obtain detailed molecular-level static structure (for example in biology), there are very few tools to develop an understanding of how these structures change dynamically as they fulfill their biological function. New biologically-compatible, high-speed nanoscale characterization technologies are required to perform these measurements. In this project, we will develop a nanowire-based, high-speed atomic force microscope (NW-HS-AFM) capable of imaging the dynamics of molecular processes on living cells. We will use this instrument to study the dynamic pore-formation mechanisms of novel peptide antibiotics. This increase in performance over current AFMs will be achieved through the use of electron-beam-deposited nanogranular tunneling resistors on prefabricated nanowire AFM cantilevers. By combining these cantilevers with our state of the art high-speed AFM technology, we expect to obtain nanoscale-resolution images of protein pores on living cells at rates of tens of milliseconds per image. This capability will open a whole new arena for seeing nanoscale life in action.
Summary
Short summary:
The ability to measure structures with nanoscale resolution continues to transform physics, materials science and life science alike. Nevertheless, while there are excellent tools to obtain detailed molecular-level static structure (for example in biology), there are very few tools to develop an understanding of how these structures change dynamically as they fulfill their biological function. New biologically-compatible, high-speed nanoscale characterization technologies are required to perform these measurements. In this project, we will develop a nanowire-based, high-speed atomic force microscope (NW-HS-AFM) capable of imaging the dynamics of molecular processes on living cells. We will use this instrument to study the dynamic pore-formation mechanisms of novel peptide antibiotics. This increase in performance over current AFMs will be achieved through the use of electron-beam-deposited nanogranular tunneling resistors on prefabricated nanowire AFM cantilevers. By combining these cantilevers with our state of the art high-speed AFM technology, we expect to obtain nanoscale-resolution images of protein pores on living cells at rates of tens of milliseconds per image. This capability will open a whole new arena for seeing nanoscale life in action.
Max ERC Funding
1 264 640 €
Duration
Start date: 2012-12-01, End date: 2017-11-30
Project acronym NANOSQUID
Project Scanning Nano-SQUID on a Tip
Researcher (PI) Eli Zeldov
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2008-AdG
Summary At the boundaries of physics research it is constantly necessary to introduce new tools and methods to expand the horizons and address fundamental issues. In this proposal, we will develop and then apply radically new tools that will enable groundbreaking progress in the field of vortex matter in superconductors and will be of great importance to condensed matter physics and nanoscience. We propose a new scanning magnetic imaging method based on self-aligned fabrication of Josephson junctions with characteristic sizes of 10 nm and superconducting quantum interference devices (SQUID) with typical diameter of 100 nm on the end of a pulled quartz tip. Such nano-SQUID on a tip will provide high-sensitivity high-bandwidth mapping of static and dynamic magnetic fields on nanometer scale that is significantly beyond the state of the art. We will develop a new washboard frequency dynamic microscopy for imaging of site-dependent vortex velocities over a remarkable range of over six orders of magnitude in velocity that is expected to reveal the most interesting dynamic phenomena in vortex mater that could not be investigated so far. Our study will provide a novel bottom-up comprehension of microscopic vortex dynamics from single vortex up to numerous predicted dynamic phase transitions, including disorder-dependent depinning processes, plastic deformations, channel flow, metastabilities and memory effects, moving smectic, moving Bragg glass, and dynamic melting. We will also develop a hybrid technology that combines a single electron transistor with nano-SQUID which will provide an unprecedented simultaneous nanoscale imaging of magnetic and electric fields. Using these tools we will carry out innovative studies of additional nano-systems and exciting quantum phenomena, including quantum tunneling in molecular magnets, spin injection and magnetic domain wall dynamics, vortex charge, unconventional superconductivity, and coexistence of superconductivity and ferromagnetism.
Summary
At the boundaries of physics research it is constantly necessary to introduce new tools and methods to expand the horizons and address fundamental issues. In this proposal, we will develop and then apply radically new tools that will enable groundbreaking progress in the field of vortex matter in superconductors and will be of great importance to condensed matter physics and nanoscience. We propose a new scanning magnetic imaging method based on self-aligned fabrication of Josephson junctions with characteristic sizes of 10 nm and superconducting quantum interference devices (SQUID) with typical diameter of 100 nm on the end of a pulled quartz tip. Such nano-SQUID on a tip will provide high-sensitivity high-bandwidth mapping of static and dynamic magnetic fields on nanometer scale that is significantly beyond the state of the art. We will develop a new washboard frequency dynamic microscopy for imaging of site-dependent vortex velocities over a remarkable range of over six orders of magnitude in velocity that is expected to reveal the most interesting dynamic phenomena in vortex mater that could not be investigated so far. Our study will provide a novel bottom-up comprehension of microscopic vortex dynamics from single vortex up to numerous predicted dynamic phase transitions, including disorder-dependent depinning processes, plastic deformations, channel flow, metastabilities and memory effects, moving smectic, moving Bragg glass, and dynamic melting. We will also develop a hybrid technology that combines a single electron transistor with nano-SQUID which will provide an unprecedented simultaneous nanoscale imaging of magnetic and electric fields. Using these tools we will carry out innovative studies of additional nano-systems and exciting quantum phenomena, including quantum tunneling in molecular magnets, spin injection and magnetic domain wall dynamics, vortex charge, unconventional superconductivity, and coexistence of superconductivity and ferromagnetism.
Max ERC Funding
2 000 000 €
Duration
Start date: 2008-12-01, End date: 2013-11-30
Project acronym NEUTRAL
Project Neutral Quasi-Particles in Mesoscopic Physics
Researcher (PI) Mordehai (Moty) Heiblum
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary I propose to study ‘neutral excitations’ in 2d and 1d electronic systems. Such excitations, rarely studied, are unique since they are chargeless but may carry energy. Being byproducts of electron interaction, they come in a few flavors: (i) Downstream modes in composite edge channels of the integer quantum Hall effect (IQHE) regime; (ii) Upstream modes in the fractional quantum Hall effect (FQHE) regime; and (iii) Zero energy Majorana states (localized or propagating quasi-particles), in non-abelian FQHE states and in 1d topological P-wave superconductors. My main interests in neutral modes in the QHE regime are: (a) Their direct association with the nature of the wavefunction of the quantum state; (b) Being excited when a charge mode is being partitioned (say, by a quantum point contact), they may play a prime role in dephasing interference of quasi-particles due to the energy they rob (in the partitioning process). As for detecting Majorana quasi-particles, and aside from the exciting physics, their non-abelian nature makes them attractive as building blocks in ‘decoherence resistant’ systems. Based on our acquired abilities, such as material growth, processing techniques, and sensitive measurement techniques, I plan to perform experiments, which include: thorough studies of downstream and upstream neutral modes via shot noise and thermoelectric current measurements; proving (or disproving) their involvement in dephasing fractionally charged quasi-particles; growing and processing structures that harbor Majorana states (in 1d nano-wires and in 2d FQHE regime; and, possibly, eventually, manipulate Majorana states (by coupling and braiding). Experiments will employ, e.g., ultra-low temperatures, sensitive shot noise measurements, cross-correlation of current fluctuations, and interference of quasi-particles (charge and neutral) in novel interferometers.
Summary
I propose to study ‘neutral excitations’ in 2d and 1d electronic systems. Such excitations, rarely studied, are unique since they are chargeless but may carry energy. Being byproducts of electron interaction, they come in a few flavors: (i) Downstream modes in composite edge channels of the integer quantum Hall effect (IQHE) regime; (ii) Upstream modes in the fractional quantum Hall effect (FQHE) regime; and (iii) Zero energy Majorana states (localized or propagating quasi-particles), in non-abelian FQHE states and in 1d topological P-wave superconductors. My main interests in neutral modes in the QHE regime are: (a) Their direct association with the nature of the wavefunction of the quantum state; (b) Being excited when a charge mode is being partitioned (say, by a quantum point contact), they may play a prime role in dephasing interference of quasi-particles due to the energy they rob (in the partitioning process). As for detecting Majorana quasi-particles, and aside from the exciting physics, their non-abelian nature makes them attractive as building blocks in ‘decoherence resistant’ systems. Based on our acquired abilities, such as material growth, processing techniques, and sensitive measurement techniques, I plan to perform experiments, which include: thorough studies of downstream and upstream neutral modes via shot noise and thermoelectric current measurements; proving (or disproving) their involvement in dephasing fractionally charged quasi-particles; growing and processing structures that harbor Majorana states (in 1d nano-wires and in 2d FQHE regime; and, possibly, eventually, manipulate Majorana states (by coupling and braiding). Experiments will employ, e.g., ultra-low temperatures, sensitive shot noise measurements, cross-correlation of current fluctuations, and interference of quasi-particles (charge and neutral) in novel interferometers.
Max ERC Funding
2 428 042 €
Duration
Start date: 2014-03-01, End date: 2019-02-28
Project acronym NonlinearTopo
Project Nonlinear Optical and Electrical Phenomena in Topological Semimetals
Researcher (PI) Binghai Yan
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary In the past decade, the band-structure topology and related topological materials have been intensively studied mostly by revealing their unique surface states. The current proposal sets a new paradigm by focusing on nonlinear optical phenomena in topological semimetals (TSMs). I aim to investigate the photocurrent and second-harmonic generation, as well as to discover novel nonlinear effects. The strength of TSMs lies in the fact that the giant Berry curvature in their band-crossing regions (e.g., Weyl points) can strongly boost these nonlinear effects, such as inducing a colossal photocurrent. Current understanding of the photocurrent is based on a model that considers the two-band transition within a Weyl cone. In the field of nonlinear optics, however, it is known that the photocurrent largely comes from three-band virtual transitions. Unfortunately, the nonlinear optics theory cannot be simply applied to TSMs due to the unphysical divergence of the photocurrent at band-crossing points. Therefore, I propose to bring the concept of three-band transitions to TSMs by reformulating the photocurrent theory framework. The new methodology represents the challenging and ground-breaking nature of the current proposal. Beyond the optical excitation, I further propose to explore exotic nonlinear electric and thermoelectric phenomena at the zero-frequency limit. I aim to build up a diagnostic tool that explores the nonlinear phenomena in a vast number of real TSM materials and directly probe the bulk topology by investigating their nonlinear properties. For example, my recent results have exposed a new group of Weyl points in a well-known Weyl semimetal by analysing the photocurrent distribution in its band structure. External perturbations can sensitively modify the TSM band structure, hence tune the induced photocurrent. This controllable photocurrent opens the door for novel device concepts, such as an optoelectronic transistor controlled by an external magnetic field.
Summary
In the past decade, the band-structure topology and related topological materials have been intensively studied mostly by revealing their unique surface states. The current proposal sets a new paradigm by focusing on nonlinear optical phenomena in topological semimetals (TSMs). I aim to investigate the photocurrent and second-harmonic generation, as well as to discover novel nonlinear effects. The strength of TSMs lies in the fact that the giant Berry curvature in their band-crossing regions (e.g., Weyl points) can strongly boost these nonlinear effects, such as inducing a colossal photocurrent. Current understanding of the photocurrent is based on a model that considers the two-band transition within a Weyl cone. In the field of nonlinear optics, however, it is known that the photocurrent largely comes from three-band virtual transitions. Unfortunately, the nonlinear optics theory cannot be simply applied to TSMs due to the unphysical divergence of the photocurrent at band-crossing points. Therefore, I propose to bring the concept of three-band transitions to TSMs by reformulating the photocurrent theory framework. The new methodology represents the challenging and ground-breaking nature of the current proposal. Beyond the optical excitation, I further propose to explore exotic nonlinear electric and thermoelectric phenomena at the zero-frequency limit. I aim to build up a diagnostic tool that explores the nonlinear phenomena in a vast number of real TSM materials and directly probe the bulk topology by investigating their nonlinear properties. For example, my recent results have exposed a new group of Weyl points in a well-known Weyl semimetal by analysing the photocurrent distribution in its band structure. External perturbations can sensitively modify the TSM band structure, hence tune the induced photocurrent. This controllable photocurrent opens the door for novel device concepts, such as an optoelectronic transistor controlled by an external magnetic field.
Max ERC Funding
1 721 706 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym NWScan
Project Bottom-up Nanowires as Scanning Multifunctional Sensors
Researcher (PI) Martino Poggio
Host Institution (HI) UNIVERSITAT BASEL
Call Details Starting Grant (StG), PE3, ERC-2013-StG
Summary Advances in growth and fabrication of semiconductor nanostructures have led to both the production of exquisitely sensitive force transducers and the development of solid-state quantum devices. Force transducers, typically monolithic Si cantilevers, are central to techniques such as AFM, and MFM. On the other hand, quantum devices including quantum wells, quantum dots (QDs), and single electron transistors are essential to technologies like lasers, optical detectors, and in experiments on quantum information. These two types of devices have – until now – occupied distinct material systems and have, for the most part, not been combined.
New developments in the growth of inorganic nanowires (NWs), however, are set to change the status quo. Researchers can now grow nanoscale structures from the bottom-up with unprecedented mechanical properties. Unlike traditional top-down cantilevers, which are etched or milled out of a larger block of material, bottom-up structures are assembled unit-by-unit to be almost defect-free on the atomic-scale. This near perfection gives NWs a much smaller mechanical dissipation than their top-down counterparts, while their higher resonance frequencies allow them to couple less strongly to common sources of noise. Meanwhile, layer-by-layer growth of NWs is rapidly developing such that both axial and radial heterostructures have now been realized. Such fine control allows for band-structure engineering and the production of devices including FETs, single photon sources, and QDs. NWs are also attractive hosts for optical emitters as their geometry favors the efficient extraction of photons.
These properties and the fact that a NW can be integrated as the tip of an SPM make NWs extremely promising devices. We propose to develop the use of NWs as scanning multifunctional sensors. We intend to 1) use NW cantilevers as force transducers in high-resolution scanning force microscopy, and 2) use NW quantum devices as scanning sensors.
Summary
Advances in growth and fabrication of semiconductor nanostructures have led to both the production of exquisitely sensitive force transducers and the development of solid-state quantum devices. Force transducers, typically monolithic Si cantilevers, are central to techniques such as AFM, and MFM. On the other hand, quantum devices including quantum wells, quantum dots (QDs), and single electron transistors are essential to technologies like lasers, optical detectors, and in experiments on quantum information. These two types of devices have – until now – occupied distinct material systems and have, for the most part, not been combined.
New developments in the growth of inorganic nanowires (NWs), however, are set to change the status quo. Researchers can now grow nanoscale structures from the bottom-up with unprecedented mechanical properties. Unlike traditional top-down cantilevers, which are etched or milled out of a larger block of material, bottom-up structures are assembled unit-by-unit to be almost defect-free on the atomic-scale. This near perfection gives NWs a much smaller mechanical dissipation than their top-down counterparts, while their higher resonance frequencies allow them to couple less strongly to common sources of noise. Meanwhile, layer-by-layer growth of NWs is rapidly developing such that both axial and radial heterostructures have now been realized. Such fine control allows for band-structure engineering and the production of devices including FETs, single photon sources, and QDs. NWs are also attractive hosts for optical emitters as their geometry favors the efficient extraction of photons.
These properties and the fact that a NW can be integrated as the tip of an SPM make NWs extremely promising devices. We propose to develop the use of NWs as scanning multifunctional sensors. We intend to 1) use NW cantilevers as force transducers in high-resolution scanning force microscopy, and 2) use NW quantum devices as scanning sensors.
Max ERC Funding
1 480 680 €
Duration
Start date: 2013-11-01, End date: 2018-10-31
Project acronym PARATOP
Project New paradigms for correlated quantum matter:Hierarchical topology, Kondo topological metals, and deep learning
Researcher (PI) Titus NEUPERT
Host Institution (HI) UNIVERSITAT ZURICH
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary Discovering, classifying and understanding phases of quantum matter is a core goal of condensed matter physics. Next to the notion of symmetry breaking phases, the concept of topological phases of matter is a prevailing theme of recent research. Topological phases are envisioned for various applications due to their universal and robust properties, such as protected conducting boundary modes, and provoke fundamental questions about the nature of many-body quantum states by providing the basis for exotic quasiparticles.
In this ERC research project, I propose several new topological phases and novel numerical approaches for studying and classifying the most sought-after topological phases of matter. Concretely, I propose the concept of three-dimensional hierarchical topological insulators, which, in contrast to the known topological phases, do not posses gapless surface, but protected gapless edge modes. Moreover, I plan to study topological metals arising in strongly correlated Kondo systems, going beyond the current paradigm of considering topological metals that arise in the absence of electronic correlations. Furthermore, I propose to make the analogous step for topological superconductors, which have been studied as free models to search for Majorana quasiparticles: For the first time, I want to explore strongly interacting systems that realize the more powerful parafermion quasiparticles with numerical techniques. Finally, in a cross-disciplinary and exploratory sub-project, I will employ methods of deep neural networks to classify strongly correlated quantum phases using supervised learning combined with a technique called deep dreaming.
Each of these sub-projects has the potential to make a paradigm-changing contribution to the study of strongly correlated and topological states of quantum matter and the combination of them allows to take advantage of synergy effects and a balance between high-risk and definitely feasible key developments.
Summary
Discovering, classifying and understanding phases of quantum matter is a core goal of condensed matter physics. Next to the notion of symmetry breaking phases, the concept of topological phases of matter is a prevailing theme of recent research. Topological phases are envisioned for various applications due to their universal and robust properties, such as protected conducting boundary modes, and provoke fundamental questions about the nature of many-body quantum states by providing the basis for exotic quasiparticles.
In this ERC research project, I propose several new topological phases and novel numerical approaches for studying and classifying the most sought-after topological phases of matter. Concretely, I propose the concept of three-dimensional hierarchical topological insulators, which, in contrast to the known topological phases, do not posses gapless surface, but protected gapless edge modes. Moreover, I plan to study topological metals arising in strongly correlated Kondo systems, going beyond the current paradigm of considering topological metals that arise in the absence of electronic correlations. Furthermore, I propose to make the analogous step for topological superconductors, which have been studied as free models to search for Majorana quasiparticles: For the first time, I want to explore strongly interacting systems that realize the more powerful parafermion quasiparticles with numerical techniques. Finally, in a cross-disciplinary and exploratory sub-project, I will employ methods of deep neural networks to classify strongly correlated quantum phases using supervised learning combined with a technique called deep dreaming.
Each of these sub-projects has the potential to make a paradigm-changing contribution to the study of strongly correlated and topological states of quantum matter and the combination of them allows to take advantage of synergy effects and a balance between high-risk and definitely feasible key developments.
Max ERC Funding
1 362 401 €
Duration
Start date: 2018-01-01, End date: 2022-12-31
Project acronym PHONUIT
Project Phononic Circuits: manipulation and coherent control of phonons
Researcher (PI) Ilaria ZARDO
Host Institution (HI) UNIVERSITAT BASEL
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary In the last decades, the power to control photons and electrons paved the way for extraordinary technological developments in electronic and optoelectronic applications. The same degree of control is still lacking with quantized lattice vibrations, i.e. phonons. Phonons are the carriers of heat and sound. The understanding and ability to manipulate phonons as quantum particles in solids enable the control of coherent phonon transport, which is of fundamental interest and could also be exploited in applications. Logic operations can be realized with the manipulation of phonons both in their coherent and incoherent form in order to switch, amplify, and route signals, and to store information. If brought to a mature level, phononic devices can become complementary to the conventional electronics, opening new opportunities.
I envision to realize each part of this technology exploiting phonons and to bring them together in an integrated circuit on chip: a phononic integrated circuit. The objective of the proposal is:
A: the realization of coherent phonon source and detector;
B: the realization of phonon computation with the use of thermal logic gates;
C: the realization of phonon based quantum and thermal memories.
To this end it is crucial to engineer nanoscale heterostructures with suitable interfaces, and to engineer the phonon spectrum and the interface thermal resistance. Phonons will be launched, probed and manipulated with a combination of pump-probe experiments and resistive thermal measurements on chip.
The proposed research will be of great relevance for fundamental research as well as for technological applications in the field of sound and thermal management.
Summary
In the last decades, the power to control photons and electrons paved the way for extraordinary technological developments in electronic and optoelectronic applications. The same degree of control is still lacking with quantized lattice vibrations, i.e. phonons. Phonons are the carriers of heat and sound. The understanding and ability to manipulate phonons as quantum particles in solids enable the control of coherent phonon transport, which is of fundamental interest and could also be exploited in applications. Logic operations can be realized with the manipulation of phonons both in their coherent and incoherent form in order to switch, amplify, and route signals, and to store information. If brought to a mature level, phononic devices can become complementary to the conventional electronics, opening new opportunities.
I envision to realize each part of this technology exploiting phonons and to bring them together in an integrated circuit on chip: a phononic integrated circuit. The objective of the proposal is:
A: the realization of coherent phonon source and detector;
B: the realization of phonon computation with the use of thermal logic gates;
C: the realization of phonon based quantum and thermal memories.
To this end it is crucial to engineer nanoscale heterostructures with suitable interfaces, and to engineer the phonon spectrum and the interface thermal resistance. Phonons will be launched, probed and manipulated with a combination of pump-probe experiments and resistive thermal measurements on chip.
The proposed research will be of great relevance for fundamental research as well as for technological applications in the field of sound and thermal management.
Max ERC Funding
1 488 388 €
Duration
Start date: 2018-01-01, End date: 2022-12-31
Project acronym PHOTOMETA
Project Photonic Metamaterials: From Basic Research to Applications
Researcher (PI) Costas Soukoulis
Host Institution (HI) IDRYMA TECHNOLOGIAS KAI EREVNAS
Call Details Advanced Grant (AdG), PE3, ERC-2012-ADG_20120216
Summary Novel artificial materials (photonic crystals (PCs), negative index materials (NIMs), and plasmonics) enable the realization of innovative EM properties unattainable in naturally existing materials. These materials, called metamaterials (MMs), have been in the foreground of scientific interest in the last ten years. However, many serious obstacles must be overcome before the impressive possibilities of MMs, especially in the optical regime, become real applications.
The present project combines NIMs, PCs, and aspects of plasmonics in a unified way in order to promote the development of functional MMs, and mainly functional optical MMs (OMMs). It identifies the main obstacles, proposes specific approaches to deal with them, and intends to study unexplored capabilities of OMMs. The project objectives are: (a) Design and realization of 3d OMMs, and achieve new metasurface designs applying Babinet’s principle. (b) Understanding and reducing the losses in OMM by incorporating gain and EM induced transparency (EIT). (c) Achieving highly efficient PC nanolasers and surface plasmons (SPs) lasers. (d) Use chiral MMs and SPs to reduce and manipulate Casimir forces, and (e) Using MMs, combined with nonlinear materials, for THz generation, and tunable response.(f)Calculate electron- phonon scattering and edge collisions in graphene and in graphene-based molecules. The unifying link in all these objectives is the endowment of photons with novel properties through imaginative use of EM-field / artificial-matter interactions. Some of these objectives seem almost certainly realizable; others are more risky but with higher reward if accomplished; some are directed towards new specific applications, while others explore new physical reality.
The accomplishment of those objectives requires novel ideas, advanced computational techniques, nanofabrication approaches, and testing. The broad expertise of the PI and his team, and their pioneering contributions to NIMs, PCs, and plasmonics qualifies them for facing the challenges and ensuring the maximum possible success of the project.
Summary
Novel artificial materials (photonic crystals (PCs), negative index materials (NIMs), and plasmonics) enable the realization of innovative EM properties unattainable in naturally existing materials. These materials, called metamaterials (MMs), have been in the foreground of scientific interest in the last ten years. However, many serious obstacles must be overcome before the impressive possibilities of MMs, especially in the optical regime, become real applications.
The present project combines NIMs, PCs, and aspects of plasmonics in a unified way in order to promote the development of functional MMs, and mainly functional optical MMs (OMMs). It identifies the main obstacles, proposes specific approaches to deal with them, and intends to study unexplored capabilities of OMMs. The project objectives are: (a) Design and realization of 3d OMMs, and achieve new metasurface designs applying Babinet’s principle. (b) Understanding and reducing the losses in OMM by incorporating gain and EM induced transparency (EIT). (c) Achieving highly efficient PC nanolasers and surface plasmons (SPs) lasers. (d) Use chiral MMs and SPs to reduce and manipulate Casimir forces, and (e) Using MMs, combined with nonlinear materials, for THz generation, and tunable response.(f)Calculate electron- phonon scattering and edge collisions in graphene and in graphene-based molecules. The unifying link in all these objectives is the endowment of photons with novel properties through imaginative use of EM-field / artificial-matter interactions. Some of these objectives seem almost certainly realizable; others are more risky but with higher reward if accomplished; some are directed towards new specific applications, while others explore new physical reality.
The accomplishment of those objectives requires novel ideas, advanced computational techniques, nanofabrication approaches, and testing. The broad expertise of the PI and his team, and their pioneering contributions to NIMs, PCs, and plasmonics qualifies them for facing the challenges and ensuring the maximum possible success of the project.
Max ERC Funding
2 100 000 €
Duration
Start date: 2013-03-01, End date: 2019-02-28
Project acronym PICOPROP
Project Photo Induced Collective Properties of Hybrid Halide Perovskites
Researcher (PI) Laszlo Forro
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Advanced Grant (AdG), PE3, ERC-2014-ADG
Summary The recent discovery of the organo-inorganic perovskite CH3NH3PbI3 as very efficient material in photoelectric conversion is multifaceted: it turns out that this compound is promising not only in photovoltaics, but it is lasing, it gives bright light emitting diodes, promising in water splitting and we are persuaded that it can play an important role in basic sciences, as well.
We have recently realized that under white light illumination the photoelectrons, due to their very long recombination time, stay in the conduction band and the resistivity of a single crystal shows a metallic behavior. If the lifetime is sufficiently long and the density of these excited carrier is high enough they could condense into a Fermi sea. The project’s goal is to realize this highly unusual state and to document its properties by magneto-transport and spectroscopic techniques. We will check in our model compound the long-sought superconductivity of photo-excited carriers, extensively searched for in cuprates, if we could stabilize it by fine tuning the interactions by hydrostatic pressure under constant illumination.
The availability of high quality samples is primordial for this program. It turns out that CH3NH3PbI3 is ideal compound, it seems to be almost free of charged defects (its room temperature resistance is 5 orders of magnitude higher than that of Phosphorus doped Silicon at 1013 cm-3 doping concentration) and we can grow excellent single crystals of it. Furthermore, it has a flexibility in material design: one can vary all the constituents, and even the dimensionality by making layered materials with the main chemical motifs. A special effort will be devoted to tune the spin-orbit coupling by different elements, since this could be at the origin of the long recombination time of the photo-electrons.
We suspect that the highly tunable, clean and disorder-free doping obtained by shining light on these ionic crystals opens a new era in material discovery.
Summary
The recent discovery of the organo-inorganic perovskite CH3NH3PbI3 as very efficient material in photoelectric conversion is multifaceted: it turns out that this compound is promising not only in photovoltaics, but it is lasing, it gives bright light emitting diodes, promising in water splitting and we are persuaded that it can play an important role in basic sciences, as well.
We have recently realized that under white light illumination the photoelectrons, due to their very long recombination time, stay in the conduction band and the resistivity of a single crystal shows a metallic behavior. If the lifetime is sufficiently long and the density of these excited carrier is high enough they could condense into a Fermi sea. The project’s goal is to realize this highly unusual state and to document its properties by magneto-transport and spectroscopic techniques. We will check in our model compound the long-sought superconductivity of photo-excited carriers, extensively searched for in cuprates, if we could stabilize it by fine tuning the interactions by hydrostatic pressure under constant illumination.
The availability of high quality samples is primordial for this program. It turns out that CH3NH3PbI3 is ideal compound, it seems to be almost free of charged defects (its room temperature resistance is 5 orders of magnitude higher than that of Phosphorus doped Silicon at 1013 cm-3 doping concentration) and we can grow excellent single crystals of it. Furthermore, it has a flexibility in material design: one can vary all the constituents, and even the dimensionality by making layered materials with the main chemical motifs. A special effort will be devoted to tune the spin-orbit coupling by different elements, since this could be at the origin of the long recombination time of the photo-electrons.
We suspect that the highly tunable, clean and disorder-free doping obtained by shining light on these ionic crystals opens a new era in material discovery.
Max ERC Funding
2 495 712 €
Duration
Start date: 2015-09-01, End date: 2020-08-31
Project acronym Piko
Project Revealing the adaptive internal organization and dynamics of bacteria and mitochondria
Researcher (PI) Suliana MANLEY
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary Bacteria cells appear to be less complex than our own cells -- yet they are better able to survive harsh conditions. Typically ~1 micron in size, they lack motor proteins; thus, they rely on fluctuations for intracellular transport. Bacteria in the environment often face starvation and exist in a non-proliferating quiescent state, which promotes antibiotic resistance and virulence. Entering quiescence, the bacterial cytoplasm displays signatures of the colloidal glass transition, with increasingly slow and heterogeneous diffusion. Also important for fitness during starvation is the formation of storage granules up to hundreds of nanometers in size. The complex state behavior of the bacterial cytoplasm is therefore important for their survival, but the physical nature of each of these processes is poorly understood. Our own cells are typically tens of microns in size and contain organelles including mitochondria, which originated from ancient bacterial endosymbionts. But little is known about the transport properties of the mitochondrial matrix, or how it responds to changes in mitochondrial membrane potential or energy production.
The goal of this project is to elucidate the organization and dynamics of the bacterial cytoplasm and the mitochondrial matrix. A major obstacle to studying the interior of bacteria and mitochondria is the relevant length scales, which lie below the diffraction limit. Furthermore, to observe and quantify their adaptive response, many cells must be measured. Our strategy to overcome both of these technical challenges is to use high-throughput super-resolution fluorescence microscopy. We have developed new microscopes, capable of capturing thousands of super-resolved cells in each experiment. We propose to translate these developments to dynamic structured illumination and long-term molecular tracking. Broadly applicable, this will also enable the quantitative study of the subcellular properties of single bacteria cells or mitochondria.
Summary
Bacteria cells appear to be less complex than our own cells -- yet they are better able to survive harsh conditions. Typically ~1 micron in size, they lack motor proteins; thus, they rely on fluctuations for intracellular transport. Bacteria in the environment often face starvation and exist in a non-proliferating quiescent state, which promotes antibiotic resistance and virulence. Entering quiescence, the bacterial cytoplasm displays signatures of the colloidal glass transition, with increasingly slow and heterogeneous diffusion. Also important for fitness during starvation is the formation of storage granules up to hundreds of nanometers in size. The complex state behavior of the bacterial cytoplasm is therefore important for their survival, but the physical nature of each of these processes is poorly understood. Our own cells are typically tens of microns in size and contain organelles including mitochondria, which originated from ancient bacterial endosymbionts. But little is known about the transport properties of the mitochondrial matrix, or how it responds to changes in mitochondrial membrane potential or energy production.
The goal of this project is to elucidate the organization and dynamics of the bacterial cytoplasm and the mitochondrial matrix. A major obstacle to studying the interior of bacteria and mitochondria is the relevant length scales, which lie below the diffraction limit. Furthermore, to observe and quantify their adaptive response, many cells must be measured. Our strategy to overcome both of these technical challenges is to use high-throughput super-resolution fluorescence microscopy. We have developed new microscopes, capable of capturing thousands of super-resolved cells in each experiment. We propose to translate these developments to dynamic structured illumination and long-term molecular tracking. Broadly applicable, this will also enable the quantitative study of the subcellular properties of single bacteria cells or mitochondria.
Max ERC Funding
2 366 835 €
Duration
Start date: 2019-10-01, End date: 2024-09-30
Project acronym POLARITRONICS
Project Manipulation of trapped quantum polariton fluids
Researcher (PI) Benoît Deveaud
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary Despite their incredibly short lifetime, around a few picoseconds only, it has now been amply demonstrated that polaritons may undergo Bose Einstein condensation (BEC) and such quantum fluids have demonstrated very interesting properties such as superfluidity. This project aims at introducing a new paradigm in solid-state physics trough the manipulation of polaritons quantum fluids and condensates in properly designed traps : such fluids will bring a wide variety of novel properties. With my team, I have recently made major advances towards this by preparing high quality polariton traps and evidencing some of the aspects of the rich physics of polaritons fluids in traps.
The whole field of polariton fluids is still in its infancy and I am convinced that major discoveries will be made during the coming years both for propagating polariton fluids and for confined geometries. I intend to stay at the forefront the field of confined polaritons and to provide high quality structures to other labs. My studies will be oriented along three major lines, each requesting a significant effort.
- The study of polariton BECs and quantum fluids in planar microcavities, both in II-VIs and III-Vs,
- The manipulation of coherent polariton fluids in geometry controlled environments,
- The realization of BEC and quantum fluid based polaritronic devices.
Each of these three parts represents a major challenge with great potentialities. First, these topics are a really novel contribution in solid-state physics. Second, the possible manipulation of polariton condensates opens up a vast domain, which covers both fundamental and applied physics and which limits we are absolutely unable to assess yet. I feel that the transition from atom condensates to polariton condensates may bring similar improvements for possible devices than it has been the case for the transition between the electronic tube and the transistor. I aim to keep my research group at the head of these very promising changes.
Summary
Despite their incredibly short lifetime, around a few picoseconds only, it has now been amply demonstrated that polaritons may undergo Bose Einstein condensation (BEC) and such quantum fluids have demonstrated very interesting properties such as superfluidity. This project aims at introducing a new paradigm in solid-state physics trough the manipulation of polaritons quantum fluids and condensates in properly designed traps : such fluids will bring a wide variety of novel properties. With my team, I have recently made major advances towards this by preparing high quality polariton traps and evidencing some of the aspects of the rich physics of polaritons fluids in traps.
The whole field of polariton fluids is still in its infancy and I am convinced that major discoveries will be made during the coming years both for propagating polariton fluids and for confined geometries. I intend to stay at the forefront the field of confined polaritons and to provide high quality structures to other labs. My studies will be oriented along three major lines, each requesting a significant effort.
- The study of polariton BECs and quantum fluids in planar microcavities, both in II-VIs and III-Vs,
- The manipulation of coherent polariton fluids in geometry controlled environments,
- The realization of BEC and quantum fluid based polaritronic devices.
Each of these three parts represents a major challenge with great potentialities. First, these topics are a really novel contribution in solid-state physics. Second, the possible manipulation of polariton condensates opens up a vast domain, which covers both fundamental and applied physics and which limits we are absolutely unable to assess yet. I feel that the transition from atom condensates to polariton condensates may bring similar improvements for possible devices than it has been the case for the transition between the electronic tube and the transistor. I aim to keep my research group at the head of these very promising changes.
Max ERC Funding
2 000 000 €
Duration
Start date: 2012-02-01, End date: 2017-01-31
Project acronym POLTDES
Project Interacting polaritons in two-dimensional electron systems
Researcher (PI) Atac Imamoglu
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2014-ADG
Summary Reversible coupling of excitons and photons in a microcavity leads to the formation of mixed light-matter quasiparticles, called cavity-polaritons. Weakly interacting polaritons constitute a rich system for studying nonequilibrium condensation and superfluidity. While exciton-polaritons have been studied mostly in intrinsic semiconductors with no free electrons, two-dimensional modulation-doped semiconductors with strong interactions between electrons have played a central role in unravelling many-body physics using transport. In this project, we combine these two fields of research and explore the complex interplay between cavity-polaritons and strongly correlated states of two dimensional electrons embedded inside microcavities. Our principal objective is the realization of polariton mediated superconductivity of electrons in gallium arsenide. Besides demonstrating a new mechanism for Cooper-pair formation, such an observation could revolutionize the search for systems that exhibit topological order. In a reciprocal approach, we will exploit the many-body nature of optical excitations in a two-dimensional electron gas to enhance polariton-polariton interactions. This will allow us to reach the polariton blockade regime, paving the way for realization of nonequilibrium strongly interacting polaritons. In parallel, we will explore cavity-magneto-polariton excitations out of fractional quantum Hall ground states: the objective in this part is to use the strong filling factor dependence of polariton splitting to realize nonlinear optical devices which derive their photon-photon interaction from light-absorption induced transition between compressible and incompressible ground states. Concurrently, we will study charged-exciton-polaritons in monolayer transition metal dichalcogenides positioned inside a microcavity, where a large polariton Berry-curvature allows for the observation of valley Hall effect and could be used to realize topological polaritons.
Summary
Reversible coupling of excitons and photons in a microcavity leads to the formation of mixed light-matter quasiparticles, called cavity-polaritons. Weakly interacting polaritons constitute a rich system for studying nonequilibrium condensation and superfluidity. While exciton-polaritons have been studied mostly in intrinsic semiconductors with no free electrons, two-dimensional modulation-doped semiconductors with strong interactions between electrons have played a central role in unravelling many-body physics using transport. In this project, we combine these two fields of research and explore the complex interplay between cavity-polaritons and strongly correlated states of two dimensional electrons embedded inside microcavities. Our principal objective is the realization of polariton mediated superconductivity of electrons in gallium arsenide. Besides demonstrating a new mechanism for Cooper-pair formation, such an observation could revolutionize the search for systems that exhibit topological order. In a reciprocal approach, we will exploit the many-body nature of optical excitations in a two-dimensional electron gas to enhance polariton-polariton interactions. This will allow us to reach the polariton blockade regime, paving the way for realization of nonequilibrium strongly interacting polaritons. In parallel, we will explore cavity-magneto-polariton excitations out of fractional quantum Hall ground states: the objective in this part is to use the strong filling factor dependence of polariton splitting to realize nonlinear optical devices which derive their photon-photon interaction from light-absorption induced transition between compressible and incompressible ground states. Concurrently, we will study charged-exciton-polaritons in monolayer transition metal dichalcogenides positioned inside a microcavity, where a large polariton Berry-curvature allows for the observation of valley Hall effect and could be used to realize topological polaritons.
Max ERC Funding
2 482 250 €
Duration
Start date: 2015-11-01, End date: 2020-10-31
Project acronym PORABEL
Project Nanopore integrated nanoelectrodes for biomolecular manipulation and sensing
Researcher (PI) Aleksandra Radenovic
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Starting Grant (StG), PE3, ERC-2010-StG_20091028
Summary In this proposal we aim to address several complex biophysical problems at single molecule level that remained elusive due to the lack of appropriate experimental approach where one could manipulate independently both interacting biomolecules and in the same time measure the strength of their interaction and correlate it with their electronic signature. In particular we are interested in finding out how biopolymer finds, enters and translocates nanopore. Equally intriguing is still unresolved mechanism of phage DNA ejection. We will also investigate how exactly proteins recognize the target binding places on DNA and if the protein DNA recognition is based on the complementarity of their charge patterns.
To allow addressing those biophysical problems we will develop novel experimental framework by integrating electrodes to the nanopore based force spectroscopy. The proposed strategy will enable two directions of the research: single molecule manipulation and single molecule detection /sensing equally suitable for investigating complex biophysical problems and molecular recognition assays.
By exploiting superior sensing and detection capabilities of our devices, we will investigate following practical applications improved nucleotide detection, selective protein detection and protein charge profiling via nanopore unfolding.
Unique combination of optical manipulation and nanofluidics could lead to new methods of bioanalysis, mechanical characterization and discrimination between specific and non-specific DNA protein interactions. This research proposal combines nanofabrication, optics, nano/microfluidics, electronics, computer programming, and biochemistry
Summary
In this proposal we aim to address several complex biophysical problems at single molecule level that remained elusive due to the lack of appropriate experimental approach where one could manipulate independently both interacting biomolecules and in the same time measure the strength of their interaction and correlate it with their electronic signature. In particular we are interested in finding out how biopolymer finds, enters and translocates nanopore. Equally intriguing is still unresolved mechanism of phage DNA ejection. We will also investigate how exactly proteins recognize the target binding places on DNA and if the protein DNA recognition is based on the complementarity of their charge patterns.
To allow addressing those biophysical problems we will develop novel experimental framework by integrating electrodes to the nanopore based force spectroscopy. The proposed strategy will enable two directions of the research: single molecule manipulation and single molecule detection /sensing equally suitable for investigating complex biophysical problems and molecular recognition assays.
By exploiting superior sensing and detection capabilities of our devices, we will investigate following practical applications improved nucleotide detection, selective protein detection and protein charge profiling via nanopore unfolding.
Unique combination of optical manipulation and nanofluidics could lead to new methods of bioanalysis, mechanical characterization and discrimination between specific and non-specific DNA protein interactions. This research proposal combines nanofabrication, optics, nano/microfluidics, electronics, computer programming, and biochemistry
Max ERC Funding
1 439 840 €
Duration
Start date: 2010-10-01, End date: 2015-09-30
Project acronym PrISMoID
Project Photonic Structural Materials with Controlled Disorder
Researcher (PI) Ullrich STEINER
Host Institution (HI) UNIVERSITE DE FRIBOURG
Call Details Advanced Grant (AdG), PE3, ERC-2018-ADG
Summary "Structural colour reflected by photonic materials is typically attributed to highly ordered nanostructures with periodicities on the 100-nm length scale. When investigating structural colour in animals and plants, it is however becoming increasingly evident that brilliant photonic colour can also arise from seemingly disordered morphologies. This is surprising as uncontrolled disorder in photonic materials usually severely degrades their colour response. While some recent theories exist, the emergence of structural colour from disordered morphologies is fundamentally not understood. It is clear however that these disordered morphologies must possess ""hidden correlations"", which enable the formation of a photonic band gap.
This project will uncover the design rules that underlie disordered photonic morphologies, thereby contributing to the fundamental understanding of photonic materials. The project has a strong nature-inspired component, but will go beyond the examination of natural photonic materials. WP1 and WP2 will examine 3D and 2D disordered photonic morphologies in animals and plants, respectively. The structural analysis of these materials will uncover hidden correlations in seemingly random morphologies. WP2 and WP3 will manufacture materials that implement these correlations to recreate the optical signatures of the biological model organisms. This will test the statistical analysis of WP1 and WP2 and shed light on the \textit{in vivo} synthesis of the disordered photonic morphologies. WP4 ties WP1-WP3 together by performing optical experiments and computer simulations. By analysing both the far- and near-field results of the simulations and comparing them with the structural correlations and optical experiments, the four WPs will not only provide a fundamental understanding of the interplay of structural correlations with optical interference in disordered materials, it will also establish design rules allowing their facile manufacture."
Summary
"Structural colour reflected by photonic materials is typically attributed to highly ordered nanostructures with periodicities on the 100-nm length scale. When investigating structural colour in animals and plants, it is however becoming increasingly evident that brilliant photonic colour can also arise from seemingly disordered morphologies. This is surprising as uncontrolled disorder in photonic materials usually severely degrades their colour response. While some recent theories exist, the emergence of structural colour from disordered morphologies is fundamentally not understood. It is clear however that these disordered morphologies must possess ""hidden correlations"", which enable the formation of a photonic band gap.
This project will uncover the design rules that underlie disordered photonic morphologies, thereby contributing to the fundamental understanding of photonic materials. The project has a strong nature-inspired component, but will go beyond the examination of natural photonic materials. WP1 and WP2 will examine 3D and 2D disordered photonic morphologies in animals and plants, respectively. The structural analysis of these materials will uncover hidden correlations in seemingly random morphologies. WP2 and WP3 will manufacture materials that implement these correlations to recreate the optical signatures of the biological model organisms. This will test the statistical analysis of WP1 and WP2 and shed light on the \textit{in vivo} synthesis of the disordered photonic morphologies. WP4 ties WP1-WP3 together by performing optical experiments and computer simulations. By analysing both the far- and near-field results of the simulations and comparing them with the structural correlations and optical experiments, the four WPs will not only provide a fundamental understanding of the interplay of structural correlations with optical interference in disordered materials, it will also establish design rules allowing their facile manufacture."
Max ERC Funding
2 499 990 €
Duration
Start date: 2019-09-01, End date: 2024-08-31
Project acronym QMES
Project Quantum Mesoscopics with Vacuum Trapped Nanoparticles
Researcher (PI) Lukas Novotny
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary "The objective of this project is to control the dynamics of a nanoscale object with unprecedented precision and to study interactions on the mesoscale, - the grey zone between the discrete atomistic world and the continuous world of macroscopic objects.
A single nanoparticle will be captured by the gradient force of a focused laser beam in ultrahigh vacuum and its center-of-mass motion will be controlled by optical back-action. To cool the nanoparticle to its quantum ground state we will explore active parametric feedback cooling in combination with passive cavity-based cooling.
A laser-trapped nanoparticle is physically decoupled from its environment, which guarantees extremely long coherence times and quality factors as high as 10^11 in ultrahigh vacuum. Force sensitivities of 10^(-20) Newtons in a bandwidth of 1 Hz can be achieved, which outperforms other measurement techniques by orders of magnitude. In this project, we will use a laser-trapped nanoparticle as a local probe for measuring mesoscopic interactions, such as Casimir forces, vacuum friction, non-equilibrium dynamics and phase transitions, with unprecedented accuracy.
We will also measure the dynamics of nanoparticles in double-well potentials created by two laser beams with closely spaced foci. A pair of trapped nanoparticles defines a highly controllable coupled-oscillator model, which can be used for studying strong coupling, level splitting, and adiabatic energy transfer at the quantum - classical barrier.
A nanoparticle cooled to its quantum ground state opens up a plethora of fundamental studies, such as the collapse of quantum superposition states under the influence of noise and gravity-induced quantum state reduction. This project will also open up new directions for precision metrology and provide unprecedented control over the dynamics of matter on the nanometer scale."
Summary
"The objective of this project is to control the dynamics of a nanoscale object with unprecedented precision and to study interactions on the mesoscale, - the grey zone between the discrete atomistic world and the continuous world of macroscopic objects.
A single nanoparticle will be captured by the gradient force of a focused laser beam in ultrahigh vacuum and its center-of-mass motion will be controlled by optical back-action. To cool the nanoparticle to its quantum ground state we will explore active parametric feedback cooling in combination with passive cavity-based cooling.
A laser-trapped nanoparticle is physically decoupled from its environment, which guarantees extremely long coherence times and quality factors as high as 10^11 in ultrahigh vacuum. Force sensitivities of 10^(-20) Newtons in a bandwidth of 1 Hz can be achieved, which outperforms other measurement techniques by orders of magnitude. In this project, we will use a laser-trapped nanoparticle as a local probe for measuring mesoscopic interactions, such as Casimir forces, vacuum friction, non-equilibrium dynamics and phase transitions, with unprecedented accuracy.
We will also measure the dynamics of nanoparticles in double-well potentials created by two laser beams with closely spaced foci. A pair of trapped nanoparticles defines a highly controllable coupled-oscillator model, which can be used for studying strong coupling, level splitting, and adiabatic energy transfer at the quantum - classical barrier.
A nanoparticle cooled to its quantum ground state opens up a plethora of fundamental studies, such as the collapse of quantum superposition states under the influence of noise and gravity-induced quantum state reduction. This project will also open up new directions for precision metrology and provide unprecedented control over the dynamics of matter on the nanometer scale."
Max ERC Funding
2 499 471 €
Duration
Start date: 2013-10-01, End date: 2018-09-30
Project acronym QON
Project Quantum optics using nanostructures: from many-body physics to quantum information processing
Researcher (PI) Atac Imamoglu
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Advanced Grant (AdG), PE3, ERC-2008-AdG
Summary Spins in nanostructures have emerged as a new paradigm for studying quantum optical phenomena in the solid-state. Motivated by potential applications in quantum information processing, the research in this field has focused on isolating a single confined spin from its environment and implementing coherent manipulation. On the other hand, it has been realized that the principal decoherence mechanisms for confined spins, stemming from interactions with nuclear or electron spin reservoirs, are intimately linked to fascinating many-body condensed-matter physics. We propose to use quantum optical techniques to investigate physics of nanostructures in two opposite but equally interesting regimes, where reservoir couplings are either suppressed to facilitate coherent control or enhanced to promote many body effects. The principal focus of our investigation of many-body phenomena will be on the first observation of optical signatures of the Kondo effect arising from exchange coupling between a confined spin and an electron spin reservoir. In addition, we propose to study nonequilibrium dynamics of quantum dot nuclear spins as well as strongly correlated system of interacting polaritons in coupled nano-cavities. To minimize spin decoherence and to implement quantum control, we propose to use nano-cavity assisted optical manipulation of two-electron spin states in double quantum dots; thanks to its resilience against spin decoherence, this system should allow us to realize elementary quantum information tasks such as spin-polarization conversion and spin entanglement. In addition to indium/gallium arsenide based structures, we propose to study semiconducting carbon nanotubes where hyperfine interactions that lead to spin decoherence can be avoided. Our nanotube experiments will focus on understanding the elementary quantum optical properties, with the ultimate goal of demonstrating coherent optical spin manipulation.
Summary
Spins in nanostructures have emerged as a new paradigm for studying quantum optical phenomena in the solid-state. Motivated by potential applications in quantum information processing, the research in this field has focused on isolating a single confined spin from its environment and implementing coherent manipulation. On the other hand, it has been realized that the principal decoherence mechanisms for confined spins, stemming from interactions with nuclear or electron spin reservoirs, are intimately linked to fascinating many-body condensed-matter physics. We propose to use quantum optical techniques to investigate physics of nanostructures in two opposite but equally interesting regimes, where reservoir couplings are either suppressed to facilitate coherent control or enhanced to promote many body effects. The principal focus of our investigation of many-body phenomena will be on the first observation of optical signatures of the Kondo effect arising from exchange coupling between a confined spin and an electron spin reservoir. In addition, we propose to study nonequilibrium dynamics of quantum dot nuclear spins as well as strongly correlated system of interacting polaritons in coupled nano-cavities. To minimize spin decoherence and to implement quantum control, we propose to use nano-cavity assisted optical manipulation of two-electron spin states in double quantum dots; thanks to its resilience against spin decoherence, this system should allow us to realize elementary quantum information tasks such as spin-polarization conversion and spin entanglement. In addition to indium/gallium arsenide based structures, we propose to study semiconducting carbon nanotubes where hyperfine interactions that lead to spin decoherence can be avoided. Our nanotube experiments will focus on understanding the elementary quantum optical properties, with the ultimate goal of demonstrating coherent optical spin manipulation.
Max ERC Funding
2 300 000 €
Duration
Start date: 2008-11-01, End date: 2013-10-31
Project acronym QTONE
Project Quantum Plasmomechanics with THz Phonons and Molecular Nano-junctions
Researcher (PI) Christophe, Marcel, Georges GALLAND
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary QTONE aims at discovering new quantum phenomena involving THz vibrational modes, and at gaining control over them using novel concepts inspired from cavity quantum optomechanics and new techniques developed for nano-plasmonics and molecular break-junctions. The three main goals of the project are:
(i) Perform optomechanical quantum information processing with THz phonons in low-dimensional systems, using a combination of ultrafast spectroscopy and time-correlated photon counting to measure quantum correlations mediated by non-classical vibrational states.
(ii) Demonstrate the feasibility of dynamical backaction amplification of THz phonons by coupling molecules and nanomaterials to plasmonic cavities and by leveraging exciton-phonon coupling to realize exciton-assisted optomechanics.
(iii) Interrogate and drive a single-molecule inside a plasmonic nanocavity using simultaneous inelastic electron tunneling and Raman spectroscopies in a molecular break-junction with engineered plasmonic resonance.
I anticipate that this project will have widespread impacts on our understanding of quantum phenomena in molecular-scale oscillators, and will foster the excellence of Europe in fields ranging from fundamental science to quantum technologies and molecular electronics.
Summary
QTONE aims at discovering new quantum phenomena involving THz vibrational modes, and at gaining control over them using novel concepts inspired from cavity quantum optomechanics and new techniques developed for nano-plasmonics and molecular break-junctions. The three main goals of the project are:
(i) Perform optomechanical quantum information processing with THz phonons in low-dimensional systems, using a combination of ultrafast spectroscopy and time-correlated photon counting to measure quantum correlations mediated by non-classical vibrational states.
(ii) Demonstrate the feasibility of dynamical backaction amplification of THz phonons by coupling molecules and nanomaterials to plasmonic cavities and by leveraging exciton-phonon coupling to realize exciton-assisted optomechanics.
(iii) Interrogate and drive a single-molecule inside a plasmonic nanocavity using simultaneous inelastic electron tunneling and Raman spectroscopies in a molecular break-junction with engineered plasmonic resonance.
I anticipate that this project will have widespread impacts on our understanding of quantum phenomena in molecular-scale oscillators, and will foster the excellence of Europe in fields ranging from fundamental science to quantum technologies and molecular electronics.
Max ERC Funding
2 437 500 €
Duration
Start date: 2019-08-01, End date: 2024-07-31
Project acronym QUANT-DES-CNT
Project Quantum Design in Carbon Nanotubes
Researcher (PI) Shahal Ilani
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Starting Grant (StG), PE3, ERC-2010-StG_20091028
Summary Quantum design, the ability to control the microscopic properties of a quantum system, has proven to be an invaluable tool in experimental physics. Carbon nanotubes are an ideal system to implement quantum design in the solid-state; their strongly interacting electrons, unusual spin properties, and unique mechanical qualities make them an excellent platform for studying quantum phenomena in low dimensions. However, for many years this potential has been hindered by the dominance of strong electronic disorder in this
system. Fortunately, a series of recent breakthroughs in making nanotubes free of disorder has dramatically changed this situation, opening up a wide range of opportunities for high-precision experiments in these systems.
In this work I propose to develop a new technology that will enable quantum design experiments in
carbon nanotubes. This technology, which builds on my recent development of ultra-clean electronic devices in nanotubes, will allow us to create nanotube device-architectures that go far beyond those currently available. Specifically, we will be able to control the properties of individual electrons with microscopic precision (~100nm), manipulate their quantum states, and image their individual wavefunctions. This new toolset will be used to study previously unexplored realms in condensed matter physics, ranging from the correlated states-of-matter formed by electrons in one-dimension, to quantum information experiments with multiple electronic spins, and finally to mechanical studies of nanotube resonators in the quantum limit.
These studies will address some of the most fundamental aspects pertaining to the physics of electrons, spins and phonons in low dimensions.
Summary
Quantum design, the ability to control the microscopic properties of a quantum system, has proven to be an invaluable tool in experimental physics. Carbon nanotubes are an ideal system to implement quantum design in the solid-state; their strongly interacting electrons, unusual spin properties, and unique mechanical qualities make them an excellent platform for studying quantum phenomena in low dimensions. However, for many years this potential has been hindered by the dominance of strong electronic disorder in this
system. Fortunately, a series of recent breakthroughs in making nanotubes free of disorder has dramatically changed this situation, opening up a wide range of opportunities for high-precision experiments in these systems.
In this work I propose to develop a new technology that will enable quantum design experiments in
carbon nanotubes. This technology, which builds on my recent development of ultra-clean electronic devices in nanotubes, will allow us to create nanotube device-architectures that go far beyond those currently available. Specifically, we will be able to control the properties of individual electrons with microscopic precision (~100nm), manipulate their quantum states, and image their individual wavefunctions. This new toolset will be used to study previously unexplored realms in condensed matter physics, ranging from the correlated states-of-matter formed by electrons in one-dimension, to quantum information experiments with multiple electronic spins, and finally to mechanical studies of nanotube resonators in the quantum limit.
These studies will address some of the most fundamental aspects pertaining to the physics of electrons, spins and phonons in low dimensions.
Max ERC Funding
1 499 940 €
Duration
Start date: 2011-01-01, End date: 2015-12-31
Project acronym QUEST
Project Quantum Entanglement in Electronic Solid State Devices
Researcher (PI) Christian Schoenenberger
Host Institution (HI) UNIVERSITAT BASEL
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary "The quantum world is by far larger than the classical one. It is entanglement, closely linked to non-locality, that spans this larger space manifold. Entanglement plays a central role in emerging quantum technology aiming to harvest quantum space. From the experimentalist’s point of view working in nanoelectronics, there is no instrument on the shelf yet, that would measure the degree of entanglement. This we would like to change with QUEST.
QUEST is a long term project with the goal to experimentally establish a continuous probe of entanglement generation in the electrical signal of quantum devices. It is set up in two parts: the realization of a highly efficient source of spin-entangled electron pairs and the exploration of different correlation measurements providing a measure of entanglement “on the fly”. During the last decade a wealth of theory proposals have appeared, addressing entanglement in electronic devices. The interaction of particles in solid-state devices provides a natural force for the appearance of entanglement. Examples are correlation between electrons and holes in the emission on a tunnel junction, or the “naturally” occurring Cooper pairs in s-wave superconductors. While first results on the realization of sources of entangled electron pairs have appeared recently, there are no experiments demonstrating entanglement in transport of any of those devices. We aim to change this and propose to implement high-bandwidth current correlation methods up to the forth moment, enabling to test Bell-inequality and quantum state tomo-graphy. Based on our long standing experience in the measurement of second-order correlations in nanodevices, we are well prepared for this very challenging goal."
Summary
"The quantum world is by far larger than the classical one. It is entanglement, closely linked to non-locality, that spans this larger space manifold. Entanglement plays a central role in emerging quantum technology aiming to harvest quantum space. From the experimentalist’s point of view working in nanoelectronics, there is no instrument on the shelf yet, that would measure the degree of entanglement. This we would like to change with QUEST.
QUEST is a long term project with the goal to experimentally establish a continuous probe of entanglement generation in the electrical signal of quantum devices. It is set up in two parts: the realization of a highly efficient source of spin-entangled electron pairs and the exploration of different correlation measurements providing a measure of entanglement “on the fly”. During the last decade a wealth of theory proposals have appeared, addressing entanglement in electronic devices. The interaction of particles in solid-state devices provides a natural force for the appearance of entanglement. Examples are correlation between electrons and holes in the emission on a tunnel junction, or the “naturally” occurring Cooper pairs in s-wave superconductors. While first results on the realization of sources of entangled electron pairs have appeared recently, there are no experiments demonstrating entanglement in transport of any of those devices. We aim to change this and propose to implement high-bandwidth current correlation methods up to the forth moment, enabling to test Bell-inequality and quantum state tomo-graphy. Based on our long standing experience in the measurement of second-order correlations in nanodevices, we are well prepared for this very challenging goal."
Max ERC Funding
1 999 350 €
Duration
Start date: 2012-04-01, End date: 2017-03-31
Project acronym See-1D-Qmatter
Project Unravelling Fragile 1D Quantum States of Matter Through Ultra-sensitive Imaging
Researcher (PI) Shahal Ilani
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Consolidator Grant (CoG), PE3, ERC-2014-CoG
Summary In condensed matter physics there are several iconic predictions that have evaded experimental discovery for many decades. Well-known examples include the proposed fractionally-charged quasiparticles in one-dimension, the theorized quantum crystal of electrons, and the elusive Kondo cloud. These sought-after many-body states all share two key aspects underscoring why they are so hard to discover: They each involve a fragile quantum state of matter that is destroyed easily by disorder or elevated temperatures, and in each case the distinguishing fingerprint is encoded in their real-space structure, which is often difficult to probe directly. The discovery of such phases therefore requires two challenging experimental components: A superb material system in which these phases can be generated, and a novel real-space probe that can image their spatial structure, yet is minimally invasive as not to destroy them.
Recently, we have developed a radically new approach for creating the state-of-the-art in both material systems and scanning probes, based on carbon nanotube devices of unprecedented complexity and cleanliness. With these components in place, we are poised to make the next quantum leap in technology by building a conceptually new experimental platform in which fragile quantum states of matter can be realized and studied microscopically: We will use a nanotube single-electron-transistor as a high-resolution, ultrasensitive scanning charge detector to non-invasively image an exotic quantum state within a second pristine nanotube. With this new platform we will thus be able to address several foundational questions in condensed matter physics (including those mentioned above) and unravel their underlying physics.
Summary
In condensed matter physics there are several iconic predictions that have evaded experimental discovery for many decades. Well-known examples include the proposed fractionally-charged quasiparticles in one-dimension, the theorized quantum crystal of electrons, and the elusive Kondo cloud. These sought-after many-body states all share two key aspects underscoring why they are so hard to discover: They each involve a fragile quantum state of matter that is destroyed easily by disorder or elevated temperatures, and in each case the distinguishing fingerprint is encoded in their real-space structure, which is often difficult to probe directly. The discovery of such phases therefore requires two challenging experimental components: A superb material system in which these phases can be generated, and a novel real-space probe that can image their spatial structure, yet is minimally invasive as not to destroy them.
Recently, we have developed a radically new approach for creating the state-of-the-art in both material systems and scanning probes, based on carbon nanotube devices of unprecedented complexity and cleanliness. With these components in place, we are poised to make the next quantum leap in technology by building a conceptually new experimental platform in which fragile quantum states of matter can be realized and studied microscopically: We will use a nanotube single-electron-transistor as a high-resolution, ultrasensitive scanning charge detector to non-invasively image an exotic quantum state within a second pristine nanotube. With this new platform we will thus be able to address several foundational questions in condensed matter physics (including those mentioned above) and unravel their underlying physics.
Max ERC Funding
2 475 000 €
Duration
Start date: 2016-01-01, End date: 2020-12-31