Project acronym ATOMION
Project Exploring hybrid quantum systems of ultracold atoms and ions
Researcher (PI) Michael Karl Koehl
Host Institution (HI) RHEINISCHE FRIEDRICH-WILHELMS-UNIVERSITAT BONN
Call Details Starting Grant (StG), PE2, ERC-2009-StG
Summary We propose to investigate hybrid quantum systems composed of ultracold atoms and ions. The mutual interaction of the cold neutral atoms and the trapped ion offers a wealth of interesting new physical problems. They span from ultracold quantum chemistry over new concepts for quantum information processing to genuine quantum many-body physics. We plan to explore aspects of quantum chemistry with ultracold atoms and ions to obtain a full understanding of the interactions in this hybrid system. We will investigate the regime of low energy collisions and search for Feshbach resonances to tune the interaction strength between atoms and ions. Moreover, we will study collective effects in chemical reactions between a Bose-Einstein condensate and a single ion. Taking advantage of the extraordinary properties of the atom-ion mixture quantum information processing with hybrid systems will be performed. In particular, we plan to realize sympathetic ground state cooling of the ion with a Bose-Einstein condensate. When the ion is immersed into the ultracold neutral atom environment the nature of the decoherence will be tailored by tuning properties of the environment: A dissipative quantum phase transition is predicted when the ion is coupled to a one-dimensional Bose gas. Moreover, we plan to realize a scalable hybrid quantum processor composed of a single ion and an array of neutral atoms in an optical lattice. The third direction we will pursue is related to impurity effects in quantum many-body physics. We plan to study transport through a single impurity or atomic quantum dot with the goal of realizing a single atom transistor. A single atom transistor transfers the quantum state of the impurity coherently to a macroscopic neutral atom current. Finally, we plan to observe Anderson s orthogonality catastrophe in which the presence of a single impurity in a quantum gas orthogonalizes the quantum many-body function of a quantum state with respect to the unperturbed one.
Summary
We propose to investigate hybrid quantum systems composed of ultracold atoms and ions. The mutual interaction of the cold neutral atoms and the trapped ion offers a wealth of interesting new physical problems. They span from ultracold quantum chemistry over new concepts for quantum information processing to genuine quantum many-body physics. We plan to explore aspects of quantum chemistry with ultracold atoms and ions to obtain a full understanding of the interactions in this hybrid system. We will investigate the regime of low energy collisions and search for Feshbach resonances to tune the interaction strength between atoms and ions. Moreover, we will study collective effects in chemical reactions between a Bose-Einstein condensate and a single ion. Taking advantage of the extraordinary properties of the atom-ion mixture quantum information processing with hybrid systems will be performed. In particular, we plan to realize sympathetic ground state cooling of the ion with a Bose-Einstein condensate. When the ion is immersed into the ultracold neutral atom environment the nature of the decoherence will be tailored by tuning properties of the environment: A dissipative quantum phase transition is predicted when the ion is coupled to a one-dimensional Bose gas. Moreover, we plan to realize a scalable hybrid quantum processor composed of a single ion and an array of neutral atoms in an optical lattice. The third direction we will pursue is related to impurity effects in quantum many-body physics. We plan to study transport through a single impurity or atomic quantum dot with the goal of realizing a single atom transistor. A single atom transistor transfers the quantum state of the impurity coherently to a macroscopic neutral atom current. Finally, we plan to observe Anderson s orthogonality catastrophe in which the presence of a single impurity in a quantum gas orthogonalizes the quantum many-body function of a quantum state with respect to the unperturbed one.
Max ERC Funding
1 405 000 €
Duration
Start date: 2009-10-01, End date: 2014-09-30
Project acronym ATOMPHOTONLOQIP
Project Experimental Linear Optics Quantum Information Processing with Atoms and Photons
Researcher (PI) Jian-Wei Pan
Host Institution (HI) RUPRECHT-KARLS-UNIVERSITAET HEIDELBERG
Call Details Starting Grant (StG), PE2, ERC-2007-StG
Summary Quantum information science and atom optics are among the most active fields in modern physics. In recent years, many theoretical efforts have been made to combine these two fields. Recent experimental progresses have shown the in-principle possibility to perform scalable quantum information processing (QIP) with linear optics and atomic ensembles. The main purpose of the present project is to use atomic qubits as quantum memory and exploit photonic qubits for information transfer and processing to achieve efficient linear optics QIP. On the one hand, utilizing the interaction between laser pulses and atomic ensembles we will experimentally investigate the potentials of atomic ensembles in the gas phase to build quantum repeaters for long-distance quantum communication, that is, to develop a new technological solution for quantum repeaters making use of the effective qubit-type entanglement of two cold atomic ensembles by a projective measurement of individual photons by spontaneous Raman processes. On this basis, we will further investigate the advantages of cold atoms in an optical trap to enhance the coherence time of atomic qubits beyond the threshold for scalable realization of quantum repeaters. Moreover, building on our long experience in research on multi-photon entanglement, we also plan to perform a number of significant experiments in the field of QIP with particular emphasis on fault-tolerant quantum computation, photon-loss-tolerant quantum computation and cluster-state based quantum simulation. Finally, by combining the techniques developed in the above quantum memory and multi-photon interference experiments, we will further experimentally investigate the possibility to achieve quantum teleportation between photonic and atomic qubits, quantum teleportation between remote atomic qubits and efficient entanglement generation via classical feed-forward. The techniques that will be developed in the present project will lay the basis for future large scale
Summary
Quantum information science and atom optics are among the most active fields in modern physics. In recent years, many theoretical efforts have been made to combine these two fields. Recent experimental progresses have shown the in-principle possibility to perform scalable quantum information processing (QIP) with linear optics and atomic ensembles. The main purpose of the present project is to use atomic qubits as quantum memory and exploit photonic qubits for information transfer and processing to achieve efficient linear optics QIP. On the one hand, utilizing the interaction between laser pulses and atomic ensembles we will experimentally investigate the potentials of atomic ensembles in the gas phase to build quantum repeaters for long-distance quantum communication, that is, to develop a new technological solution for quantum repeaters making use of the effective qubit-type entanglement of two cold atomic ensembles by a projective measurement of individual photons by spontaneous Raman processes. On this basis, we will further investigate the advantages of cold atoms in an optical trap to enhance the coherence time of atomic qubits beyond the threshold for scalable realization of quantum repeaters. Moreover, building on our long experience in research on multi-photon entanglement, we also plan to perform a number of significant experiments in the field of QIP with particular emphasis on fault-tolerant quantum computation, photon-loss-tolerant quantum computation and cluster-state based quantum simulation. Finally, by combining the techniques developed in the above quantum memory and multi-photon interference experiments, we will further experimentally investigate the possibility to achieve quantum teleportation between photonic and atomic qubits, quantum teleportation between remote atomic qubits and efficient entanglement generation via classical feed-forward. The techniques that will be developed in the present project will lay the basis for future large scale
Max ERC Funding
1 435 000 €
Duration
Start date: 2008-07-01, End date: 2013-12-31
Project acronym ATTOCO
Project Attosecond tracing of collective dynamics
in clusters and nanoparticles
Researcher (PI) Matthias Friedrich Kling
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Starting Grant (StG), PE2, ERC-2012-StG_20111012
Summary Collective electron motion can unfold on attosecond time scales in nanoplasmonic systems, as defined by the inverse spectral bandwidth of the plasmonic resonant region. Similarly, in dielectrics or semiconductors, the laser-driven collective motion of electrons can occur on this characteristic time scale. Until now, such collective electron dynamics has not been directly observed on its natural, attosecond timescale. In ATTOCO, the attosecond, sub-cycle dynamics of strong-field driven collective electron dynamics in clusters and nanoparticles will be explored. Moreover, we will explore field-dependent processes induced by strong laser fields in nanometer sized matter, such as the metallization of dielectrics, which has been recently proposed theoretically.
In order to map the collective electron motion we will apply the attosecond nanoplasmonic streaking technique, which has been proposed and developed theoretically. In this approach, the temporal resolution is achieved by limiting the emission of high energetic, direct photoelectrons to a sub-cycle time window using attosecond XUV pulses phase-locked to a driving few-cycle near-infrared field. Kinetic energy spectra of the photoelectrons recorded for different delays between the excitation field and the ionizing XUV pulse will allow extracting the spatio-temporal electron dynamics. ATTOCO offers the capability to measure field-induced material changes in real-time and to gain novel insight into collective electron dynamics. In particular, we aim to learn from ATTOCO in detail, how the collective electron motion is established, how the collective motion is driven by the strong external field and over which pathways and timescale the collective motion decays.
ATTOCO provides also a major step in the development of lightwave (nano-)electronics, which may push the frontiers of electronics from multi-gigahertz to petahertz frequencies. If successfully accomplished, this development will herald the potential scalability of electron-based information technologies to lightwave frequencies, surpassing the speed of current computation and communication technology by many orders of magnitude.
Summary
Collective electron motion can unfold on attosecond time scales in nanoplasmonic systems, as defined by the inverse spectral bandwidth of the plasmonic resonant region. Similarly, in dielectrics or semiconductors, the laser-driven collective motion of electrons can occur on this characteristic time scale. Until now, such collective electron dynamics has not been directly observed on its natural, attosecond timescale. In ATTOCO, the attosecond, sub-cycle dynamics of strong-field driven collective electron dynamics in clusters and nanoparticles will be explored. Moreover, we will explore field-dependent processes induced by strong laser fields in nanometer sized matter, such as the metallization of dielectrics, which has been recently proposed theoretically.
In order to map the collective electron motion we will apply the attosecond nanoplasmonic streaking technique, which has been proposed and developed theoretically. In this approach, the temporal resolution is achieved by limiting the emission of high energetic, direct photoelectrons to a sub-cycle time window using attosecond XUV pulses phase-locked to a driving few-cycle near-infrared field. Kinetic energy spectra of the photoelectrons recorded for different delays between the excitation field and the ionizing XUV pulse will allow extracting the spatio-temporal electron dynamics. ATTOCO offers the capability to measure field-induced material changes in real-time and to gain novel insight into collective electron dynamics. In particular, we aim to learn from ATTOCO in detail, how the collective electron motion is established, how the collective motion is driven by the strong external field and over which pathways and timescale the collective motion decays.
ATTOCO provides also a major step in the development of lightwave (nano-)electronics, which may push the frontiers of electronics from multi-gigahertz to petahertz frequencies. If successfully accomplished, this development will herald the potential scalability of electron-based information technologies to lightwave frequencies, surpassing the speed of current computation and communication technology by many orders of magnitude.
Max ERC Funding
1 498 500 €
Duration
Start date: 2013-06-01, End date: 2018-05-31
Project acronym ATTOELECTRONICS
Project Attoelectronics: Steering electrons in atoms and molecules with synthesized waveforms of light
Researcher (PI) Eleftherios Goulielmakis
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), PE2, ERC-2010-StG_20091028
Summary In order for electronics to meet the ever raising demands for higher speeds of operation, the dimensions of its basic elements drop continuously. This miniaturization, that will soon meet the dimensions of a single molecule or an atom, calls for new approaches in electronics that take advantage, rather than confront the dominant at these scales quantum laws.
Electronics on the scale of atoms and molecules require fields that are able to trigger and to steer electrons at speeds comparable to their intrinsic dynamics, determined by the quantum mechanical laws. For the valence electrons of atoms and molecules, this motion is clocked in tens to thousands of attoseconds, (1 as =10-18 sec) implying the potential for executing basic electronic operations in the PHz regime and beyond. This is approximately ~1000000 times faster as compared to any contemporary technology.
To meet this challenging goal, this project will utilize conceptual and technological advances of attosecond science as its primary tools. First, pulses of light, the fields of which can be sculpted and characterized with attosecond accuracy, for triggering as well as for terminating the ultrafast electron motion in an atom or a molecule. Second, attosecond pulses in the extreme ultraviolet, which can probe and frame-freeze the created electron motion, with unprecedented resolution, and determine the direction and the magnitude of the created currents.
This project will interrogate the limits of the fastest electronic motion that light fields can trigger as well as terminate, a few hundreds of attoseconds later, in an atom or a molecule. In this way it aims to explore new routes of atomic and molecular scale electronic switching at PHz frequencies.
Summary
In order for electronics to meet the ever raising demands for higher speeds of operation, the dimensions of its basic elements drop continuously. This miniaturization, that will soon meet the dimensions of a single molecule or an atom, calls for new approaches in electronics that take advantage, rather than confront the dominant at these scales quantum laws.
Electronics on the scale of atoms and molecules require fields that are able to trigger and to steer electrons at speeds comparable to their intrinsic dynamics, determined by the quantum mechanical laws. For the valence electrons of atoms and molecules, this motion is clocked in tens to thousands of attoseconds, (1 as =10-18 sec) implying the potential for executing basic electronic operations in the PHz regime and beyond. This is approximately ~1000000 times faster as compared to any contemporary technology.
To meet this challenging goal, this project will utilize conceptual and technological advances of attosecond science as its primary tools. First, pulses of light, the fields of which can be sculpted and characterized with attosecond accuracy, for triggering as well as for terminating the ultrafast electron motion in an atom or a molecule. Second, attosecond pulses in the extreme ultraviolet, which can probe and frame-freeze the created electron motion, with unprecedented resolution, and determine the direction and the magnitude of the created currents.
This project will interrogate the limits of the fastest electronic motion that light fields can trigger as well as terminate, a few hundreds of attoseconds later, in an atom or a molecule. In this way it aims to explore new routes of atomic and molecular scale electronic switching at PHz frequencies.
Max ERC Funding
1 262 000 €
Duration
Start date: 2010-12-01, End date: 2016-11-30
Project acronym BinGraSp
Project Modeling the Gravitational Spectrum of Neutron Star Binaries
Researcher (PI) Sebastiano Bernuzzi
Host Institution (HI) FRIEDRICH-SCHILLER-UNIVERSITAT JENA
Call Details Starting Grant (StG), PE2, ERC-2016-STG
Summary The most energetic electromagnetic phenomena in the Universe are believed to be powered by the collision of two neutron stars, the smallest and densest stars on which surface gravity is about 2 billion times stronger than gravity on Earth. However, a definitive identification of neutron star mergers as central engines for short-gamma-ray bursts and kilonovae transients is possible only by direct gravitational-wave observations. The latter provide us with unique information on neutron stars' masses, radii, and spins, including the possibility to set the strongest observational constraints on the unknown equation-of-state of matter at supranuclear densities.
Neutron stars binary mergers are among the main targets for ground-based gravitational-wave interferometers like Advanced LIGO and Virgo, which start operations this year. The astrophysical data analysis of the signals emitted by these sources requires the availability of accurate waveform models, which are missing to date. Hence, the theoretical understanding of the gravitational spectrum is a necessary and urgent step for the development of a gravitational-based astrophysics in the next years.
This project aims at developing, for the first time, a precise theoretical model for the complete gravitational spectrum of neutron star binaries, including the merger and postmerger stages of the coalescence process. Building on the PI's unique expertise and track record, the proposed research exploits synergy between analytical and numerical methods in General Relativity. Results from state of the art nonlinear 3D numerical relativity simulations will be combined with the most advanced analytical framework for the relativistic two-body problem. The model developed here will be used in the first gravitational-wave observations and will dramatically impact multimessenger astrophysics.
Summary
The most energetic electromagnetic phenomena in the Universe are believed to be powered by the collision of two neutron stars, the smallest and densest stars on which surface gravity is about 2 billion times stronger than gravity on Earth. However, a definitive identification of neutron star mergers as central engines for short-gamma-ray bursts and kilonovae transients is possible only by direct gravitational-wave observations. The latter provide us with unique information on neutron stars' masses, radii, and spins, including the possibility to set the strongest observational constraints on the unknown equation-of-state of matter at supranuclear densities.
Neutron stars binary mergers are among the main targets for ground-based gravitational-wave interferometers like Advanced LIGO and Virgo, which start operations this year. The astrophysical data analysis of the signals emitted by these sources requires the availability of accurate waveform models, which are missing to date. Hence, the theoretical understanding of the gravitational spectrum is a necessary and urgent step for the development of a gravitational-based astrophysics in the next years.
This project aims at developing, for the first time, a precise theoretical model for the complete gravitational spectrum of neutron star binaries, including the merger and postmerger stages of the coalescence process. Building on the PI's unique expertise and track record, the proposed research exploits synergy between analytical and numerical methods in General Relativity. Results from state of the art nonlinear 3D numerical relativity simulations will be combined with the most advanced analytical framework for the relativistic two-body problem. The model developed here will be used in the first gravitational-wave observations and will dramatically impact multimessenger astrophysics.
Max ERC Funding
1 432 301 €
Duration
Start date: 2017-10-01, End date: 2022-09-30
Project acronym CREMA
Project Charge radius experiment with muonic atoms
Researcher (PI) Randolf Pohl
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), PE2, ERC-2011-StG_20101014
Summary "A measurement of the 2S-2P transition frequencies (Lamb shift) in the muonic helium-3 and 4 ions by means of laser spectroscopy is proposed. This will lead to a ten times more accurate determination of the root-mean-square (rms) charge radii of the He-3 and He-4 nuclei. The radius of the magnetic moment distribution inside the He-3 nucleus will result from the hyperfine structure in muonic 3He.
In the muonic helium ion, a single negative muon orbits the helium nucleus. The muon is a point-like lepton, just as the electron, except it is about 200 times heavier. This gives a factor of 200^3 = 10^7 enhancement of nuclear finite size effects on the energy levels of muonic vs. regular (electonic) Helium ions. Muonic helium is the ideal sytem to study the He nuclear size.
The CREMA project has four main aims:
(1) Solve the ""proton size puzzle"" created by our recently completed muonic hydrogen project [R. Pohl et al., ""The size of the proton"", Nature 466, 213 (2010)]. Our tenfold improvement of the proton charge radius resulted in a five sigma discrepancy with the 2006 CODATA value, which is mostly based on hydrogen spectroscopy. This poses a serious challenge to bound-state QED, and may even point towards new physics. CREMA will help to clarify this.
(2) Absolute nuclear charge radii of all helium isotopes He-3,4,6,8 will result from CREMA. The charge radius differences are precisely known, but the absolute size of the He-4 anchor nucleus can best be measured in muonic helium. Absolute charge radii are a more stringent benchmark for few-nucleon nuclear models than the radius difference.
(3) Test of bound-state QED: Spectroscopy of regular He+ ions is underway. He+ (Z=2) is more sensitive than hydrogen (Z=1) to higher-order QED contributions which scale as Z^5. An accurate He charge radius from CREMA is mandatory for this.
(4) An improved value of the Rydberg constant will result from the He+ spectroscopy only with the improved charge radius from CREMA."
Summary
"A measurement of the 2S-2P transition frequencies (Lamb shift) in the muonic helium-3 and 4 ions by means of laser spectroscopy is proposed. This will lead to a ten times more accurate determination of the root-mean-square (rms) charge radii of the He-3 and He-4 nuclei. The radius of the magnetic moment distribution inside the He-3 nucleus will result from the hyperfine structure in muonic 3He.
In the muonic helium ion, a single negative muon orbits the helium nucleus. The muon is a point-like lepton, just as the electron, except it is about 200 times heavier. This gives a factor of 200^3 = 10^7 enhancement of nuclear finite size effects on the energy levels of muonic vs. regular (electonic) Helium ions. Muonic helium is the ideal sytem to study the He nuclear size.
The CREMA project has four main aims:
(1) Solve the ""proton size puzzle"" created by our recently completed muonic hydrogen project [R. Pohl et al., ""The size of the proton"", Nature 466, 213 (2010)]. Our tenfold improvement of the proton charge radius resulted in a five sigma discrepancy with the 2006 CODATA value, which is mostly based on hydrogen spectroscopy. This poses a serious challenge to bound-state QED, and may even point towards new physics. CREMA will help to clarify this.
(2) Absolute nuclear charge radii of all helium isotopes He-3,4,6,8 will result from CREMA. The charge radius differences are precisely known, but the absolute size of the He-4 anchor nucleus can best be measured in muonic helium. Absolute charge radii are a more stringent benchmark for few-nucleon nuclear models than the radius difference.
(3) Test of bound-state QED: Spectroscopy of regular He+ ions is underway. He+ (Z=2) is more sensitive than hydrogen (Z=1) to higher-order QED contributions which scale as Z^5. An accurate He charge radius from CREMA is mandatory for this.
(4) An improved value of the Rydberg constant will result from the He+ spectroscopy only with the improved charge radius from CREMA."
Max ERC Funding
1 499 976 €
Duration
Start date: 2011-11-01, End date: 2016-10-31
Project acronym CutLoops
Project Loop amplitudes in quantum field theory
Researcher (PI) Ruth Britto
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Consolidator Grant (CoG), PE2, ERC-2014-CoG
Summary The traditional formulation of relativistic quantum theory is ill-equipped to handle the range of difficult computations needed to describe particle collisions at the Large Hadron Collider (LHC) within a suitable time frame. Yet, recent work shows that probability amplitudes in quantum gauge field theories, such as those describing the Standard Model and its extensions, take surprisingly simple forms. The simplicity indicates deep structure in gauge theory that has already led to dramatic computational improvements, but remains to be fully understood. For precision calculations and investigations of the deep structure of gauge theory, a comprehensive method for computing multi-loop amplitudes systematically and efficiently must be found.
The goal of this proposal is to construct a new and complete approach to computing amplitudes from a detailed understanding of their singularities, based on prior successes of so-called on-shell methods combined with the latest developments in the mathematics of Feynman integrals. Scattering processes relevant to the LHC and to formal investigations of quantum field theory will be computed within the new framework.
Summary
The traditional formulation of relativistic quantum theory is ill-equipped to handle the range of difficult computations needed to describe particle collisions at the Large Hadron Collider (LHC) within a suitable time frame. Yet, recent work shows that probability amplitudes in quantum gauge field theories, such as those describing the Standard Model and its extensions, take surprisingly simple forms. The simplicity indicates deep structure in gauge theory that has already led to dramatic computational improvements, but remains to be fully understood. For precision calculations and investigations of the deep structure of gauge theory, a comprehensive method for computing multi-loop amplitudes systematically and efficiently must be found.
The goal of this proposal is to construct a new and complete approach to computing amplitudes from a detailed understanding of their singularities, based on prior successes of so-called on-shell methods combined with the latest developments in the mathematics of Feynman integrals. Scattering processes relevant to the LHC and to formal investigations of quantum field theory will be computed within the new framework.
Max ERC Funding
1 954 065 €
Duration
Start date: 2015-10-01, End date: 2020-09-30
Project acronym Dark-OsT
Project Experimental Searches for Oscillating and Transient effects from the Dark Sector
Researcher (PI) Dmitry Budker
Host Institution (HI) JOHANNES GUTENBERG-UNIVERSITAT MAINZ
Call Details Advanced Grant (AdG), PE2, ERC-2015-AdG
Summary The objective of the proposed project is to pioneer a magnetometry-based experimental framework for the detection of time-varying signatures of the ‘dark sector’. This novel approach will enable systematic searches for particles contributing to the dark matter and for dark-energy components.
The nature of dark matter and that of dark energy are among the central open problems in modern physics. There are only few experimental bounds and so far no conclusive observations of dark-sector particles or fields. Experiments enabling a direct coupling to the dark sector and thus a systematic search for and study of the contributing particles and fields would open up new vistas for areas ranging from particle physics to astrophysics and cosmology, and would in particular provide insights into the physics beyond the Standard Model.
Here, we propose a framework for such experimental searches based on high-precision magnetometers, and networks thereof. Our approach is distinct from existing efforts in two ways. First, it will enable searches for so-far unexplored couplings to ultra-light bosonic particles present in the Universe that could be components of dark matter and/or dark energy, in particular axions and axion-like particles (ALPs). Second, we will develop and use devices and methods tailored to search for oscillating and transient, rather than time-independent, effects. Specifically, we will use nuclear magnetic resonance (NMR) techniques for detecting spin precession caused by background axion and ALP dark matter, and geographically separated magnetometers for identify transient effects, such as crossing domain walls of ALP fields, which have been proposed as a possible dark-energy component.
The devices and methods developed in the framework of this project will provide the essential components for unique searches for a broad class of dark-matter and dark-energy candidates and might enable the key experiments to understanding the dark sector.
Summary
The objective of the proposed project is to pioneer a magnetometry-based experimental framework for the detection of time-varying signatures of the ‘dark sector’. This novel approach will enable systematic searches for particles contributing to the dark matter and for dark-energy components.
The nature of dark matter and that of dark energy are among the central open problems in modern physics. There are only few experimental bounds and so far no conclusive observations of dark-sector particles or fields. Experiments enabling a direct coupling to the dark sector and thus a systematic search for and study of the contributing particles and fields would open up new vistas for areas ranging from particle physics to astrophysics and cosmology, and would in particular provide insights into the physics beyond the Standard Model.
Here, we propose a framework for such experimental searches based on high-precision magnetometers, and networks thereof. Our approach is distinct from existing efforts in two ways. First, it will enable searches for so-far unexplored couplings to ultra-light bosonic particles present in the Universe that could be components of dark matter and/or dark energy, in particular axions and axion-like particles (ALPs). Second, we will develop and use devices and methods tailored to search for oscillating and transient, rather than time-independent, effects. Specifically, we will use nuclear magnetic resonance (NMR) techniques for detecting spin precession caused by background axion and ALP dark matter, and geographically separated magnetometers for identify transient effects, such as crossing domain walls of ALP fields, which have been proposed as a possible dark-energy component.
The devices and methods developed in the framework of this project will provide the essential components for unique searches for a broad class of dark-matter and dark-energy candidates and might enable the key experiments to understanding the dark sector.
Max ERC Funding
2 474 875 €
Duration
Start date: 2016-08-01, End date: 2021-07-31
Project acronym DG-PESP-CS
Project Deterministic Generation of Polarization Entangled single Photons Cluster States
Researcher (PI) David Gershoni
Host Institution (HI) TECHNION - ISRAEL INSTITUTE OF TECHNOLOGY
Call Details Advanced Grant (AdG), PE2, ERC-2015-AdG
Summary Measurement based quantum computing is one of the most fault-tolerant architectures proposed for quantum information processing. It opens the possibility of performing quantum computing tasks using linear optical systems. An efficient route for measurement based quantum computing utilizes highly entangled states of photons, called cluster states. Propagation and processing quantum information is made possible this way using only single qubit measurements. It is highly resilient to qubit losses. In addition, single qubit measurements of polarization qubits is easily performed with high fidelity using standard optical tools. These features make photonic clusters excellent platforms for quantum information processing.
Constructing photonic cluster states, however, is a formidable challenge, attracting vast amounts of research efforts. While in principle it is possible to build up cluster states using interferometry, such a method is of a probabilistic nature and entails a large overhead of resources. The use of entangled photon pairs reduces this overhead by a small factor only.
We outline a novel route for constructing a deterministic source of photonic cluster states using a device based on semiconductor quantum dot. Our proposal follows a suggestion by Lindner and Rudolph. We use repeated optical excitations of a long lived coherent spin confined in a single semiconductor quantum dot and demonstrate for the first time practical realization of their proposal. Our preliminary demonstration presents a breakthrough in quantum technology since deterministic source of photonic cluster, reduces the resources needed quantum information processing. It may have revolutionary prospects for technological applications as well as to our fundamental understanding of quantum systems.
We propose to capitalize on this recent breakthrough and concentrate on R&D which will further advance this forefront field of science and technology by utilizing the horizons that it opens.
Summary
Measurement based quantum computing is one of the most fault-tolerant architectures proposed for quantum information processing. It opens the possibility of performing quantum computing tasks using linear optical systems. An efficient route for measurement based quantum computing utilizes highly entangled states of photons, called cluster states. Propagation and processing quantum information is made possible this way using only single qubit measurements. It is highly resilient to qubit losses. In addition, single qubit measurements of polarization qubits is easily performed with high fidelity using standard optical tools. These features make photonic clusters excellent platforms for quantum information processing.
Constructing photonic cluster states, however, is a formidable challenge, attracting vast amounts of research efforts. While in principle it is possible to build up cluster states using interferometry, such a method is of a probabilistic nature and entails a large overhead of resources. The use of entangled photon pairs reduces this overhead by a small factor only.
We outline a novel route for constructing a deterministic source of photonic cluster states using a device based on semiconductor quantum dot. Our proposal follows a suggestion by Lindner and Rudolph. We use repeated optical excitations of a long lived coherent spin confined in a single semiconductor quantum dot and demonstrate for the first time practical realization of their proposal. Our preliminary demonstration presents a breakthrough in quantum technology since deterministic source of photonic cluster, reduces the resources needed quantum information processing. It may have revolutionary prospects for technological applications as well as to our fundamental understanding of quantum systems.
We propose to capitalize on this recent breakthrough and concentrate on R&D which will further advance this forefront field of science and technology by utilizing the horizons that it opens.
Max ERC Funding
2 502 974 €
Duration
Start date: 2016-06-01, End date: 2021-05-31
Project acronym DIVI
Project Direct Visualization of Light-Driven Atomic-Scale Carrier Dynamics in Space and Time
Researcher (PI) Peter Gerhard Baum
Host Institution (HI) UNIVERSITAT KONSTANZ
Call Details Consolidator Grant (CoG), PE2, ERC-2014-CoG
Summary Electronics is rapidly speeding up. Ultimately, miniaturization will reach atomic dimensions and the switching speed will reach optical frequencies. This ultimate regime of lightwave electronics, where atomic-scale charges are controlled by few-cycle laser fields, holds promise to advance information processing technology from today’s microwave frequencies to the thousand times faster regime of optical light fields. All materials, including dielectrics, semiconductors and molecular crystals, react to such field oscillations with an intricate interplay between atomic-scale charge displacements (polarizations) and collective carrier motion on the nanometer scale (currents). This entanglement provides a rich set of potential mechanisms for switching and control. However, our ability to eventually realize lightwave electronics, or even to make first steps, will critically depend on our ability to actually measure electronic motion in the relevant environment: within/around atoms. The most fundamental approach would be a direct visualization in space and time. This project, if realized, will offer that: a spatiotemporal recording of electronic motion with sub-atomic spatial resolution and sub-optical-cycle time resolution, i.e. picometers and few-femtoseconds/attoseconds. Drawing on our unique combination of expertise covering electron diffraction and few-cycle laser optics likewise, we will replace the photon pulses of conventional attosecond spectroscopy with freely propagating single-electron pulses at picometer de Broglie wavelength, compressed in time by sculpted laser fields. Stroboscopic diffraction/microscopy will provide, after playback of the image sequence, a direct visualization of fundamental electronic activity in space and time. Profound study of atomic-scale light-matter interaction in simple and complex materials will provide a comprehensive picture of the fundamental physics allowing or limiting the high-speed electronics of the future.
Summary
Electronics is rapidly speeding up. Ultimately, miniaturization will reach atomic dimensions and the switching speed will reach optical frequencies. This ultimate regime of lightwave electronics, where atomic-scale charges are controlled by few-cycle laser fields, holds promise to advance information processing technology from today’s microwave frequencies to the thousand times faster regime of optical light fields. All materials, including dielectrics, semiconductors and molecular crystals, react to such field oscillations with an intricate interplay between atomic-scale charge displacements (polarizations) and collective carrier motion on the nanometer scale (currents). This entanglement provides a rich set of potential mechanisms for switching and control. However, our ability to eventually realize lightwave electronics, or even to make first steps, will critically depend on our ability to actually measure electronic motion in the relevant environment: within/around atoms. The most fundamental approach would be a direct visualization in space and time. This project, if realized, will offer that: a spatiotemporal recording of electronic motion with sub-atomic spatial resolution and sub-optical-cycle time resolution, i.e. picometers and few-femtoseconds/attoseconds. Drawing on our unique combination of expertise covering electron diffraction and few-cycle laser optics likewise, we will replace the photon pulses of conventional attosecond spectroscopy with freely propagating single-electron pulses at picometer de Broglie wavelength, compressed in time by sculpted laser fields. Stroboscopic diffraction/microscopy will provide, after playback of the image sequence, a direct visualization of fundamental electronic activity in space and time. Profound study of atomic-scale light-matter interaction in simple and complex materials will provide a comprehensive picture of the fundamental physics allowing or limiting the high-speed electronics of the future.
Max ERC Funding
1 992 083 €
Duration
Start date: 2015-08-01, End date: 2020-07-31
