Project acronym ASTONISH
Project Atomic-scale STudies Of the Nature of and conditions for Inducing Superconductivity at High-temperatures
Researcher (PI) Roland Martin Wiesendanger
Host Institution (HI) UNIVERSITAET HAMBURG
Country Germany
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary "One of the greatest challenges these days in condensed matter physics is the fundamental understanding of the mechanisms leading to high-Tc superconductivity and ultimately, as a result of that, the discovery of a material system exhibiting a superconducting state with a transition temperature Tc above room temperature. While several different classes of high-Tc materials have been discovered in the past decades, including the well-known CuO-based superconductors (cuprates) or the more recently discovered class of Fe-based superconductors (pnictides), the mechanisms behind high-Tc superconductivity remain controversial. Up to date, no theory exists which would allow for a rational design of a superconducting material with a transition temperature above room temperature. On the other hand, experiments on rather complex material systems often suffer from material imperfections or from a lack of tunability of materials’ properties within a wide range. Our experimental studies within this project therefore will focus on model-type systems which can be prepared and thoroughly characterized with atomic level precision. The growth of the model-type samples will be controlled vertically one atomic layer at a time and laterally by making use of single-atom manipulation techniques. Atomic-scale characterization at low energy-scales will be performed by low-temperature spin-resolved elastic and inelastic scanning tunnelling microscopy (STM) and spectroscopy (STS) as well as by non-contact atomic force microscopy and spectroscopy based techniques. Transport experiments will be conducted by a four-probe STM setup under well-defined ultra-high vacuum conditions. By having access to the electronic and spin, as well as to the vibrational degrees of freedom down to the atomic level, we hope to be able to identify the nature of and the conditions for inducing superconductivity at high temperatures, which could ultimately lead a knowledge-based design of high-Tc superconductors."
Summary
"One of the greatest challenges these days in condensed matter physics is the fundamental understanding of the mechanisms leading to high-Tc superconductivity and ultimately, as a result of that, the discovery of a material system exhibiting a superconducting state with a transition temperature Tc above room temperature. While several different classes of high-Tc materials have been discovered in the past decades, including the well-known CuO-based superconductors (cuprates) or the more recently discovered class of Fe-based superconductors (pnictides), the mechanisms behind high-Tc superconductivity remain controversial. Up to date, no theory exists which would allow for a rational design of a superconducting material with a transition temperature above room temperature. On the other hand, experiments on rather complex material systems often suffer from material imperfections or from a lack of tunability of materials’ properties within a wide range. Our experimental studies within this project therefore will focus on model-type systems which can be prepared and thoroughly characterized with atomic level precision. The growth of the model-type samples will be controlled vertically one atomic layer at a time and laterally by making use of single-atom manipulation techniques. Atomic-scale characterization at low energy-scales will be performed by low-temperature spin-resolved elastic and inelastic scanning tunnelling microscopy (STM) and spectroscopy (STS) as well as by non-contact atomic force microscopy and spectroscopy based techniques. Transport experiments will be conducted by a four-probe STM setup under well-defined ultra-high vacuum conditions. By having access to the electronic and spin, as well as to the vibrational degrees of freedom down to the atomic level, we hope to be able to identify the nature of and the conditions for inducing superconductivity at high temperatures, which could ultimately lead a knowledge-based design of high-Tc superconductors."
Max ERC Funding
2 170 696 €
Duration
Start date: 2014-01-01, End date: 2018-12-31
Project acronym CellMechanoControl
Project The physical basis of cellular mechanochemical
control circuits
Researcher (PI) Christoph Friedrich Schmidt
Host Institution (HI) GEORG-AUGUST-UNIVERSITAT GOTTINGEN STIFTUNG OFFENTLICHEN RECHTS
Country Germany
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary Biological cells possess a chemical “sense of smell” and a physical “sense of touch”. Structure, dynamics, development, differentiation and even apoptosis of cells are guided by physical stimuli feeding into a regulatory network integrating biochemical and mechanical signals. Cells are equipped with both, force-generating structures, and stress sensors including force-sensitive structural proteins or mechanosensitive ion channels. Pathways from force sensing to structural and transcriptional controls are not yet understood.
The goal of the proposed interdisciplinary project is to quantitatively establish such pathways, connecting the statistical physics and the mechanics to the biochemistry. We will measure and model the complex non-equilibrium mechanical structures in cells, and we will study how external and cell-generated forces activate sensory processes that (i) act (back) on the morphology of the cell structures, and (ii) lead to cell-fate decisions, such as differentiation. The most prominent stress-bearing and -generating structures in cells are actin/myosin based, and the most prominent mechanoactive and -sensitive cell types are fibroblasts in connective tissue and myocytes in muscle. We will first focus on actin/myosin bundles in fibroblasts and in sarcomeres in developing heart muscle cells. We will observe cells under the influence of exactly controlled external stresses. Forces on suspended single cells or cell clusters will be exerted by laser trapping and sensitively detected by laser interferometry. We furthermore will monitor mechanically triggered transcriptional regulation by detecting mRNA in the nucleus of mouse stem cells differentiating to cardiomyocytes. We will develop fluorescent mRNA sensors that can be imaged in cells, based on near-IR fluorescent single-walled carbon nanotubes.
Understanding mechanical cell regulation has far-ranging relevance for fundamental cell biophysics, developmental biology and for human health.
Summary
Biological cells possess a chemical “sense of smell” and a physical “sense of touch”. Structure, dynamics, development, differentiation and even apoptosis of cells are guided by physical stimuli feeding into a regulatory network integrating biochemical and mechanical signals. Cells are equipped with both, force-generating structures, and stress sensors including force-sensitive structural proteins or mechanosensitive ion channels. Pathways from force sensing to structural and transcriptional controls are not yet understood.
The goal of the proposed interdisciplinary project is to quantitatively establish such pathways, connecting the statistical physics and the mechanics to the biochemistry. We will measure and model the complex non-equilibrium mechanical structures in cells, and we will study how external and cell-generated forces activate sensory processes that (i) act (back) on the morphology of the cell structures, and (ii) lead to cell-fate decisions, such as differentiation. The most prominent stress-bearing and -generating structures in cells are actin/myosin based, and the most prominent mechanoactive and -sensitive cell types are fibroblasts in connective tissue and myocytes in muscle. We will first focus on actin/myosin bundles in fibroblasts and in sarcomeres in developing heart muscle cells. We will observe cells under the influence of exactly controlled external stresses. Forces on suspended single cells or cell clusters will be exerted by laser trapping and sensitively detected by laser interferometry. We furthermore will monitor mechanically triggered transcriptional regulation by detecting mRNA in the nucleus of mouse stem cells differentiating to cardiomyocytes. We will develop fluorescent mRNA sensors that can be imaged in cells, based on near-IR fluorescent single-walled carbon nanotubes.
Understanding mechanical cell regulation has far-ranging relevance for fundamental cell biophysics, developmental biology and for human health.
Max ERC Funding
2 425 200 €
Duration
Start date: 2014-06-01, End date: 2019-05-31
Project acronym MassQ
Project Massive-Object Quantum Physics
Researcher (PI) Roman Schnabel
Host Institution (HI) UNIVERSITAET HAMBURG
Country Germany
Call Details Advanced Grant (AdG), PE2, ERC-2013-ADG
Summary The world of quantum physics is usually associated with the microscopic cosmos of atoms and photons. In principle, but so far without any demonstration, even heavy objects can exhibit the distinguished properties of quantum world particles. In 1935, Einstein, Podolsky and Rosen (EPR) challenged a particular prediction of quantum theory saying that two particles can exist in a so-called entangled state in which the two particles do not have individually defined (‘local’) positions and momenta. Most interestingly, the existence of entangled states was subsequently fully confirmed in experiments with photons and atoms.
The new project MassQ aims to test and to confirm quantum theory in the macroscopic world of massive, human-world sized objects by realizing an EPR entanglement experiment with heavy mirrors. Two kg-sized mirrors will be cooled to low temperature and their centre of mass motion driven by radiation pressure of intense laser light in such a way that the mirrors will lose their individually defined positions and momenta. As a result, their joint motion will form a unified massive quantum object.
This project will realize a fundamental test of quantum theory in the so far unexplored regime of human-world sized objects. Recent advances in gravitational wave detector research and in opto-mechanics make this project feasible. The vision of this project points even further into the future. This project aims to lay the basis for a completely new class of physics experiments. Mirrors with kilogram masses have a proper gravitational field and cause a space-time curvature in their vicinity. This way, in principle, the dynamics of two heavy entangled mirrors need to be described not only by quantum theory but also by general relativity. Today it is completely unclear what the results of such a new class of physics experiments will be. Undoubtedly, they are important to illuminate the deep connection between the two most successful theories in physics.
Summary
The world of quantum physics is usually associated with the microscopic cosmos of atoms and photons. In principle, but so far without any demonstration, even heavy objects can exhibit the distinguished properties of quantum world particles. In 1935, Einstein, Podolsky and Rosen (EPR) challenged a particular prediction of quantum theory saying that two particles can exist in a so-called entangled state in which the two particles do not have individually defined (‘local’) positions and momenta. Most interestingly, the existence of entangled states was subsequently fully confirmed in experiments with photons and atoms.
The new project MassQ aims to test and to confirm quantum theory in the macroscopic world of massive, human-world sized objects by realizing an EPR entanglement experiment with heavy mirrors. Two kg-sized mirrors will be cooled to low temperature and their centre of mass motion driven by radiation pressure of intense laser light in such a way that the mirrors will lose their individually defined positions and momenta. As a result, their joint motion will form a unified massive quantum object.
This project will realize a fundamental test of quantum theory in the so far unexplored regime of human-world sized objects. Recent advances in gravitational wave detector research and in opto-mechanics make this project feasible. The vision of this project points even further into the future. This project aims to lay the basis for a completely new class of physics experiments. Mirrors with kilogram masses have a proper gravitational field and cause a space-time curvature in their vicinity. This way, in principle, the dynamics of two heavy entangled mirrors need to be described not only by quantum theory but also by general relativity. Today it is completely unclear what the results of such a new class of physics experiments will be. Undoubtedly, they are important to illuminate the deep connection between the two most successful theories in physics.
Max ERC Funding
1 566 210 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym MOLPROCOMP
Project From Structure Property to Structure Process Property Relations in Soft Matter – a Computational Physics Approach
Researcher (PI) Kurt Kremer
Host Institution (HI) Klinik Max Planck Institut für Psychiatrie
Country Germany
Call Details Advanced Grant (AdG), PE3, ERC-2013-ADG
Summary "From cell biology to polymer photovoltaics, (self-)assembly processes that give rise to morphology and functionality result from non-equilibrium processes, which are driven by both, external forces, such as flow due to pressure gradients, inserting energy, or manipulation on a local molecular level, or internal forces, such as relaxation into a state of lower free energy. The resulting material is arrested in a metastable state. Most previous work has focused on the relationship between structure and properties, while insight into the guiding principles governing the formation of a (new) material, has been lacking. However, a comprehensive molecular level understanding of non-equilibrium assembly would allow for control and manipulation of material processes and their resulting properties. This lag of knowledge can be traced to the formidable challenge in obtaining a molecular picture of non-equilibrium assembly. Non-equilibrium processes have been studied extensively on a macroscopic level by non-equilibrium thermodynamics. We take a novel route approaching the challenge from a molecular point of view. Recent advances in experimental, but especially computational modeling, now allow to follow (supra-) molecular structural evolution across the range of length and time scales necessary to comprehend, and ultimately control and manipulate macroscopic functional properties of soft matter at the molecular level. Soft matter is particularly suited for that approach, as it is “slow” and easy to manipulate. We take the computational physics route, based on simulations on different levels of resolution (all atom, coarse grained, continuum) in combination with recent multiscale and adaptive resolution techniques. This work will initiate the way towards a paradigm change from conventional Structure Property Relations (SPR) to molecularly based Structure Process Property Relations (SPPR)."
Summary
"From cell biology to polymer photovoltaics, (self-)assembly processes that give rise to morphology and functionality result from non-equilibrium processes, which are driven by both, external forces, such as flow due to pressure gradients, inserting energy, or manipulation on a local molecular level, or internal forces, such as relaxation into a state of lower free energy. The resulting material is arrested in a metastable state. Most previous work has focused on the relationship between structure and properties, while insight into the guiding principles governing the formation of a (new) material, has been lacking. However, a comprehensive molecular level understanding of non-equilibrium assembly would allow for control and manipulation of material processes and their resulting properties. This lag of knowledge can be traced to the formidable challenge in obtaining a molecular picture of non-equilibrium assembly. Non-equilibrium processes have been studied extensively on a macroscopic level by non-equilibrium thermodynamics. We take a novel route approaching the challenge from a molecular point of view. Recent advances in experimental, but especially computational modeling, now allow to follow (supra-) molecular structural evolution across the range of length and time scales necessary to comprehend, and ultimately control and manipulate macroscopic functional properties of soft matter at the molecular level. Soft matter is particularly suited for that approach, as it is “slow” and easy to manipulate. We take the computational physics route, based on simulations on different levels of resolution (all atom, coarse grained, continuum) in combination with recent multiscale and adaptive resolution techniques. This work will initiate the way towards a paradigm change from conventional Structure Property Relations (SPR) to molecularly based Structure Process Property Relations (SPPR)."
Max ERC Funding
2 025 000 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym PACART
Project Free space photon atom coupling - the art of focusing
Researcher (PI) Gerhard Leuchs
Host Institution (HI) FRIEDRICH-ALEXANDER-UNIVERSITAET ERLANGEN-NUERNBERG
Country Germany
Call Details Advanced Grant (AdG), PE2, ERC-2013-ADG
Summary A conceptually simple but radically new approach will be explored and developed: the interaction of light with a single atom in free space. No experiment has yet come close to the highest possible coupling efficiency attainable in such a fundamental system. The usual way of enhancing light-matter coupling is to place an atom inside a cavity. Another approach involves setting the atom in the near field of a plasmonic antenna. The free space approach, however, is special: a light field matched to the atomic dipole provides many desired aspects of fully efficient coupling. The birth of this new research area was marked by the PI's pioneering publication in 2000 arguing that efficient coupling of an atom to a light field is possible in free space without modifying the density of modes of the light field such as in a cavity or having competing radiative or non-radiative decay channels such as in plasmonic enhancement. At the time of writing, the highest probability achieved for exciting a single atom with a single photon in free space is less than 1%. At the heart of the project proposed here is a deep diffraction-limited parabolic mirror, which can provide the required aberration-free focusing of a vectorial dipole wave over the full 4π solid angle – a true challenge to optics. Perfectly efficient free space coupling to a single quantum system will be a novel building block for numerous applications. In addition, the experimental set-up will allow for the studying of other open questions in the realm of classical and quantum optics related to full solid angle focusing.
Summary
A conceptually simple but radically new approach will be explored and developed: the interaction of light with a single atom in free space. No experiment has yet come close to the highest possible coupling efficiency attainable in such a fundamental system. The usual way of enhancing light-matter coupling is to place an atom inside a cavity. Another approach involves setting the atom in the near field of a plasmonic antenna. The free space approach, however, is special: a light field matched to the atomic dipole provides many desired aspects of fully efficient coupling. The birth of this new research area was marked by the PI's pioneering publication in 2000 arguing that efficient coupling of an atom to a light field is possible in free space without modifying the density of modes of the light field such as in a cavity or having competing radiative or non-radiative decay channels such as in plasmonic enhancement. At the time of writing, the highest probability achieved for exciting a single atom with a single photon in free space is less than 1%. At the heart of the project proposed here is a deep diffraction-limited parabolic mirror, which can provide the required aberration-free focusing of a vectorial dipole wave over the full 4π solid angle – a true challenge to optics. Perfectly efficient free space coupling to a single quantum system will be a novel building block for numerous applications. In addition, the experimental set-up will allow for the studying of other open questions in the realm of classical and quantum optics related to full solid angle focusing.
Max ERC Funding
1 499 704 €
Duration
Start date: 2014-03-01, End date: 2019-02-28
Project acronym SELFCOMPLETION
Project UV-Completion through Bose-Einstein Condensation: A Quantum Model of Black Holes
Researcher (PI) Georgi Dvali
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Country Germany
Call Details Advanced Grant (AdG), PE2, ERC-2013-ADG
Summary The project addresses the two greatest unresolved problems in quantum field theory and gravity.
The question of UV-completion beyond the Planck length and the mysteries of black holes. It is grounded on a recent program of research where we have put forward a fundamentally different unifying approach to both of these problems.
This approach is based on modeling Black Holes as self-sustained Bose-Einstein condensates of long wave-length gravitons with the very peculiar property of being stuck at the critical point of a quantum phase transition. This quantum model of black holes is the outcome of understanding the UV-completion of gravity not taking place at the expense of some new dynamics of very short-wavelength degrees of freedom but rather at the expense of long-wavelength collective excitations of the above graviton Bose-Einstein condensate.
Apart of being of undoubted theoretical value for our understanding of black hole physics and its role in the UV-completion, the new framework has important implications for astrophysics, for LHC searches of micro black holes and for studies of alternative UV-completions of the Standard Model, as well as for making connections between gravity and condensed matter physics, both theoretical and experimental. Our project is fully devoted to the exploration of this new framework with special emphasis in the development of concrete experimental predictions.
Summary
The project addresses the two greatest unresolved problems in quantum field theory and gravity.
The question of UV-completion beyond the Planck length and the mysteries of black holes. It is grounded on a recent program of research where we have put forward a fundamentally different unifying approach to both of these problems.
This approach is based on modeling Black Holes as self-sustained Bose-Einstein condensates of long wave-length gravitons with the very peculiar property of being stuck at the critical point of a quantum phase transition. This quantum model of black holes is the outcome of understanding the UV-completion of gravity not taking place at the expense of some new dynamics of very short-wavelength degrees of freedom but rather at the expense of long-wavelength collective excitations of the above graviton Bose-Einstein condensate.
Apart of being of undoubted theoretical value for our understanding of black hole physics and its role in the UV-completion, the new framework has important implications for astrophysics, for LHC searches of micro black holes and for studies of alternative UV-completions of the Standard Model, as well as for making connections between gravity and condensed matter physics, both theoretical and experimental. Our project is fully devoted to the exploration of this new framework with special emphasis in the development of concrete experimental predictions.
Max ERC Funding
1 167 183 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
