Project acronym ATTIDA
Project Attosecond space-time imaging of coherent quantum dynamics
Researcher (PI) Michael Krueger
Host Institution (HI) TECHNION - ISRAEL INSTITUTE OF TECHNOLOGY
Country Israel
Call Details Starting Grant (StG), PE2, ERC-2019-STG
Summary Coherence is a fundamental property of quantum mechanics, characterizing phase correlations of light or matter waves. It is at the heart of many physical phenomena, such as the creation of electron-hole pairs in the photovoltaic effect or the fast migration of electronic charge within a molecule. In order to study coherent electron dynamics, extremely high spatial and temporal resolving power is required, which is highly challenging. Well-established imaging methods like scanning tunneling microscopy achieve atomic-scale spatial resolution, while lacking ultrafast time resolution. At the temporal frontier, I recently bridged the gap between attosecond spectroscopy (1as = 10-18 s) and the nano-scale. The goal of my research program is to unlock the full potential of attosecond spectroscopy by achieving simultaneous spatial and temporal probing of ultrafast coherent phenomena.
The proposed approach relies on the introduction of attosecond spectroscopy into scanning tunneling microscopy and electron holography. The spatial resolution of these methods is based on nano-scale needle tips, serving as local probes or as point-like electron sources. My team and I will develop attosecond temporal gates at the tips, enabling pump-probe spectroscopy. The resulting “pump” – triggering the coherent dynamics – and the “probe” – measuring its evolution – are localized in space and time, with attosecond and sub-nanometer precision. This combination will allow watching charge dynamics in a single molecule and observing multi-electron dynamics in nanostructures with atomic-scale site selectivity, as they evolve in real time.
My approach has the potential to shed new light on quantum optics, plasmonics, molecular electronics, surface science and femtochemistry. In particular, my team and I will study quantum tunneling on the atomic level, charge migration in organic molecules and electron-hole dynamics in low-dimensional solid-state systems.
Summary
Coherence is a fundamental property of quantum mechanics, characterizing phase correlations of light or matter waves. It is at the heart of many physical phenomena, such as the creation of electron-hole pairs in the photovoltaic effect or the fast migration of electronic charge within a molecule. In order to study coherent electron dynamics, extremely high spatial and temporal resolving power is required, which is highly challenging. Well-established imaging methods like scanning tunneling microscopy achieve atomic-scale spatial resolution, while lacking ultrafast time resolution. At the temporal frontier, I recently bridged the gap between attosecond spectroscopy (1as = 10-18 s) and the nano-scale. The goal of my research program is to unlock the full potential of attosecond spectroscopy by achieving simultaneous spatial and temporal probing of ultrafast coherent phenomena.
The proposed approach relies on the introduction of attosecond spectroscopy into scanning tunneling microscopy and electron holography. The spatial resolution of these methods is based on nano-scale needle tips, serving as local probes or as point-like electron sources. My team and I will develop attosecond temporal gates at the tips, enabling pump-probe spectroscopy. The resulting “pump” – triggering the coherent dynamics – and the “probe” – measuring its evolution – are localized in space and time, with attosecond and sub-nanometer precision. This combination will allow watching charge dynamics in a single molecule and observing multi-electron dynamics in nanostructures with atomic-scale site selectivity, as they evolve in real time.
My approach has the potential to shed new light on quantum optics, plasmonics, molecular electronics, surface science and femtochemistry. In particular, my team and I will study quantum tunneling on the atomic level, charge migration in organic molecules and electron-hole dynamics in low-dimensional solid-state systems.
Max ERC Funding
1 690 323 €
Duration
Start date: 2020-01-01, End date: 2024-12-31
Project acronym ATTO-GRAM
Project Attosecond Gated Holography
Researcher (PI) Nirit DUDOVICH
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Country Israel
Call Details Consolidator Grant (CoG), PE2, ERC-2019-COG
Summary Strong-field-driven electric currents in condensed-matter systems open new frontiers in manipulating electronic and optical properties on petahertz frequency scales. In this regime, new challenges arise as the role of the band structure and the quantum nature of ultrafast electron-hole dynamics have yet to be resolved. While petahertz spectroscopy and control of condensed-matter systems holds great potential, revealing the underlying attosecond (1 attosecond – 10(-18) second) dynamics of electrons in solids is still in its infancy.
The proposed research aims at the development of a state-of-the-art attosecond metrology scheme that integrates the concept of holography with attosecond gating. Attosecond-gated holography will provide direct insight into the instantaneous evolution of the complex quantum wavefunctions in solid-state systems. This scheme will enable us to follow the electron-hole wavepacket evolution during ultrafast band structure deformation, probing a range of fundamental processes – from sub-cycle phase transitions to ultrafast dynamics in correlated systems. In ATTO-GRAM, we will establish attosecond-gated holography and then apply it to study field-induced transient band structures, resolve electron-hole dynamics during lattice deformation and reveal attosecond phenomena in strongly correlated systems.
Integrating state-of-the-art experimental schemes, supported by advanced theoretical analysis, will lead to the discoveries of new phenomena previously deemed inaccessible. The impact of the proposed research reaches beyond attosecond metrology – opening new routes in the establishment of compact solid-state extreme ultraviolet sources, petahertz electronics and optically induced metamaterials.
Summary
Strong-field-driven electric currents in condensed-matter systems open new frontiers in manipulating electronic and optical properties on petahertz frequency scales. In this regime, new challenges arise as the role of the band structure and the quantum nature of ultrafast electron-hole dynamics have yet to be resolved. While petahertz spectroscopy and control of condensed-matter systems holds great potential, revealing the underlying attosecond (1 attosecond – 10(-18) second) dynamics of electrons in solids is still in its infancy.
The proposed research aims at the development of a state-of-the-art attosecond metrology scheme that integrates the concept of holography with attosecond gating. Attosecond-gated holography will provide direct insight into the instantaneous evolution of the complex quantum wavefunctions in solid-state systems. This scheme will enable us to follow the electron-hole wavepacket evolution during ultrafast band structure deformation, probing a range of fundamental processes – from sub-cycle phase transitions to ultrafast dynamics in correlated systems. In ATTO-GRAM, we will establish attosecond-gated holography and then apply it to study field-induced transient band structures, resolve electron-hole dynamics during lattice deformation and reveal attosecond phenomena in strongly correlated systems.
Integrating state-of-the-art experimental schemes, supported by advanced theoretical analysis, will lead to the discoveries of new phenomena previously deemed inaccessible. The impact of the proposed research reaches beyond attosecond metrology – opening new routes in the establishment of compact solid-state extreme ultraviolet sources, petahertz electronics and optically induced metamaterials.
Max ERC Funding
2 000 000 €
Duration
Start date: 2020-01-01, End date: 2024-12-31
Project acronym Atto-Zepto
Project Ultrasensitive Nano-Optomechanical Sensors
Researcher (PI) Olivier ARCIZET
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Consolidator Grant (CoG), PE2, ERC-2018-COG
Summary By enabling the conversion of forces into measurable displacements, mechanical oscillators have always played a central role in experimental physics. Recent developments in the PI group demonstrated the possibility to realize ultrasensitive and vectorial force field sensing by using suspended SiC nanowires and optical readout of their transverse vibrations. Astonishing sensitivities were obtained at room and dilution temperatures, at the Atto- Zepto-newton level, for which the electron-electron interaction becomes detectable at 100µm.
The goal of the project is to push forward those ultrasensitive nano-optomechanical force sensors, to realize even more challenging explorations of novel fundamental interactions at the quantum-classical interface.
We will develop universal advanced sensing protocols to explore the vectorial structure of fundamental optical, electrostatic or magnetic interactions, and investigate Casimir force fields above nanostructured surfaces, in geometries where it was recently predicted to become repulsive. The second research axis is the one of cavity nano-optomechanics: inserting the ultrasensitive nanowire in a high finesse optical microcavity should enhance the light-nanowire interaction up to the point where a single cavity photon can displace the nanowire by more than its zero point quantum fluctuations. We will investigate this so-called ultrastrong optomechanical coupling regime, and further explore novel regimes in cavity optomechanics, where optical non-linearities at the single photon level become accessible. The last part is dedicated to the exploration of hybrid qubit-mechanical systems, in which nanowire vibrations are magnetically coupled to the spin of a single Nitrogen Vacancy defect in diamond. We will focus on the exploration of spin-dependent forces, aiming at mechanically detecting qubit excitations, opening a novel road towards the generation of non-classical states of motion, and mechanically enhanced quantum sensors.
Summary
By enabling the conversion of forces into measurable displacements, mechanical oscillators have always played a central role in experimental physics. Recent developments in the PI group demonstrated the possibility to realize ultrasensitive and vectorial force field sensing by using suspended SiC nanowires and optical readout of their transverse vibrations. Astonishing sensitivities were obtained at room and dilution temperatures, at the Atto- Zepto-newton level, for which the electron-electron interaction becomes detectable at 100µm.
The goal of the project is to push forward those ultrasensitive nano-optomechanical force sensors, to realize even more challenging explorations of novel fundamental interactions at the quantum-classical interface.
We will develop universal advanced sensing protocols to explore the vectorial structure of fundamental optical, electrostatic or magnetic interactions, and investigate Casimir force fields above nanostructured surfaces, in geometries where it was recently predicted to become repulsive. The second research axis is the one of cavity nano-optomechanics: inserting the ultrasensitive nanowire in a high finesse optical microcavity should enhance the light-nanowire interaction up to the point where a single cavity photon can displace the nanowire by more than its zero point quantum fluctuations. We will investigate this so-called ultrastrong optomechanical coupling regime, and further explore novel regimes in cavity optomechanics, where optical non-linearities at the single photon level become accessible. The last part is dedicated to the exploration of hybrid qubit-mechanical systems, in which nanowire vibrations are magnetically coupled to the spin of a single Nitrogen Vacancy defect in diamond. We will focus on the exploration of spin-dependent forces, aiming at mechanically detecting qubit excitations, opening a novel road towards the generation of non-classical states of motion, and mechanically enhanced quantum sensors.
Max ERC Funding
2 067 905 €
Duration
Start date: 2019-09-01, End date: 2024-08-31
Project acronym Attoclock
Project Clocking fundamental attosecond electron dynamics
Researcher (PI) Ursula Keller
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), PE2, ERC-2012-ADG_20120216
Summary The attoclock is a powerful, new, and unconventional tool to study fundamental attosecond dynamics on an atomic scale. We established its potential by using the first attoclock to measure the tunneling delay time in laser-induced ionization of helium and argon atoms, with surprising results. Building on these first proof-of-principle measurements, I propose to amplify and expand this tool concept to explore the following key questions: How fast can light liberate electrons from a single atom, a single molecule, or a solid-state system? Related are more questions: How fast can an electron tunnel through a potential barrier? How fast is a multi-photon absorption process? How fast is single-photon photoemission? Many of these questions will undoubtedly spark more questions – revealing deeper and more detailed insights on the dynamics of some of the most fundamental and relevant optoelectronic processes.
There are still many unknown and unexplored areas here. Theory has failed to offer definitive answers. Simulations based on the exact time-dependent Schrödinger equation have not been possible in most cases. Therefore one uses approximations and simpler models to capture the essential physics. Such semi-classical models potentially will help to understand attosecond energy and charge transport in larger molecular systems. Indeed the attoclock provides a unique tool to explore different semi-classical models.
For example, the question of whether electron tunneling through an energetically forbidden region takes a finite time or is instantaneous has been subject to ongoing debate for the last sixty years. The tunnelling process, charge transfer, and energy transport all play key roles in electronics, energy conversion, chemical and biological reactions, and fundamental processes important for improved information, health, and energy technologies. We believe the attoclock can help refine and resolve key models for many of these important underlying attosecond processes.
Summary
The attoclock is a powerful, new, and unconventional tool to study fundamental attosecond dynamics on an atomic scale. We established its potential by using the first attoclock to measure the tunneling delay time in laser-induced ionization of helium and argon atoms, with surprising results. Building on these first proof-of-principle measurements, I propose to amplify and expand this tool concept to explore the following key questions: How fast can light liberate electrons from a single atom, a single molecule, or a solid-state system? Related are more questions: How fast can an electron tunnel through a potential barrier? How fast is a multi-photon absorption process? How fast is single-photon photoemission? Many of these questions will undoubtedly spark more questions – revealing deeper and more detailed insights on the dynamics of some of the most fundamental and relevant optoelectronic processes.
There are still many unknown and unexplored areas here. Theory has failed to offer definitive answers. Simulations based on the exact time-dependent Schrödinger equation have not been possible in most cases. Therefore one uses approximations and simpler models to capture the essential physics. Such semi-classical models potentially will help to understand attosecond energy and charge transport in larger molecular systems. Indeed the attoclock provides a unique tool to explore different semi-classical models.
For example, the question of whether electron tunneling through an energetically forbidden region takes a finite time or is instantaneous has been subject to ongoing debate for the last sixty years. The tunnelling process, charge transfer, and energy transport all play key roles in electronics, energy conversion, chemical and biological reactions, and fundamental processes important for improved information, health, and energy technologies. We believe the attoclock can help refine and resolve key models for many of these important underlying attosecond processes.
Max ERC Funding
2 319 796 €
Duration
Start date: 2013-03-01, End date: 2018-02-28
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
Country Germany
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
Country Germany
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 ATTOSTRUCTURA
Project Structured attosecond pulses for ultrafast nanoscience
Researcher (PI) Carlos HERNANDEZ-GARCIA
Host Institution (HI) UNIVERSIDAD DE SALAMANCA
Country Spain
Call Details Starting Grant (StG), PE2, ERC-2019-STG
Summary Light is one of today’s most powerful tools for exploriLight is one of today’s most powerful tools for exploring nature at the frontier of the human knowledge. The rapid development of laser technology allow us today to generate ultrashort pulses of coherent structured light: light fields with custom spatial and temporal properties, such as intensity, phase and angular momentum. The later one represents one of the most interesting light properties nowadays, as topological light beams carrying angular momentum interact with matter differently, introducing mechanical motion to micro and nano-structures, and affecting fundamental excitation rules. High-order harmonic generation (HHG) stands as a unique mechanism to provide coherent flashes of light with outstanding properties: its radiation spectrum expands from the vacuum ultraviolet to the soft x-rays; it can be synthesized in pulses as short as several attoseconds (10^-18 seconds): and it can be structured in its angular momentum properties. This proposal represents a timely opportunity to explore the ground-breaking opportunities offered by attosecond structured x-ray sources. It conveys computing light-matter interaction in extreme conditions, which requires an extraordinary effort in the elaboration of new theoretical tools to design, propose and guide future experiments at the frontier of ultrafast science. We shall pioneer the new scenario of angular momenta in structured ultrashort x-rays –the most complex coherent pulses to date–. It is not difficult to envision a new era in ultrafast nanotechnology that makes use of these x-ray sources. In particular we shall pioneer their application to nanoscience and ultrafast magnetism. We aim to establish the grounding principles of attomagnetism, taking advantage of the unique opportunity offered by structured light pulses to induce pure attosecond magnetic fields, which could set the precedents of high-rate magnetic recording through ultrafast magnetization reversal.
Summary
Light is one of today’s most powerful tools for exploriLight is one of today’s most powerful tools for exploring nature at the frontier of the human knowledge. The rapid development of laser technology allow us today to generate ultrashort pulses of coherent structured light: light fields with custom spatial and temporal properties, such as intensity, phase and angular momentum. The later one represents one of the most interesting light properties nowadays, as topological light beams carrying angular momentum interact with matter differently, introducing mechanical motion to micro and nano-structures, and affecting fundamental excitation rules. High-order harmonic generation (HHG) stands as a unique mechanism to provide coherent flashes of light with outstanding properties: its radiation spectrum expands from the vacuum ultraviolet to the soft x-rays; it can be synthesized in pulses as short as several attoseconds (10^-18 seconds): and it can be structured in its angular momentum properties. This proposal represents a timely opportunity to explore the ground-breaking opportunities offered by attosecond structured x-ray sources. It conveys computing light-matter interaction in extreme conditions, which requires an extraordinary effort in the elaboration of new theoretical tools to design, propose and guide future experiments at the frontier of ultrafast science. We shall pioneer the new scenario of angular momenta in structured ultrashort x-rays –the most complex coherent pulses to date–. It is not difficult to envision a new era in ultrafast nanotechnology that makes use of these x-ray sources. In particular we shall pioneer their application to nanoscience and ultrafast magnetism. We aim to establish the grounding principles of attomagnetism, taking advantage of the unique opportunity offered by structured light pulses to induce pure attosecond magnetic fields, which could set the precedents of high-rate magnetic recording through ultrafast magnetization reversal.
Max ERC Funding
1 425 000 €
Duration
Start date: 2020-03-01, End date: 2025-02-28
Project acronym AuDACE
Project Attosecond Dynamics in Advanced Materials
Researcher (PI) Matteo LUCCHINI
Host Institution (HI) POLITECNICO DI MILANO
Country Italy
Call Details Starting Grant (StG), PE2, ERC-2019-STG
Summary Speed and performances of contemporary digital electronics are limited by the available device architectures and heat dissipation. Two-dimensional (2D) materials are emerging as one of the main candidates for designing new structures capable to overcome the current device limitations and foster the establishment of the electronics of the future. Due to the electron confinement in two directions, they are characterised by exotic physical, electronic and chemical properties, which are neither fully investigated nor understood. In particular, the lack of suitable tools hinders the possibility to study the ultrafast processes unfolding during light-matter interaction. Nevertheless, a clear understanding is required in order to leverage the unique properties of 2D materials. AuDACE aims to enter this unexplored region and investigate ultrafast electron, exciton and spin dynamics happening in advanced materials on time scales below few femtoseconds with unprecedented and ground-breaking possible outcome.
To reach this ambitious goal AuDACE will go beyond the state of the art and develop an innovative pump-probe beamline for transient absorption and reflectivity measurements based on arbitrarily polarised attosecond pulses in a two-foci geometry. Once the experimental techniques are established, my team and I will concentrate on ultrafast exciton dynamics in monolayer transition metal dichalcogenides (ML-TMDCs). In the final phase, AuDACE will focus on a new class of materials such as ferromagnetic ML-TMDCs to investigate the elusive physical mechanism responsible for ultrafast spin and magnetic dynamics. For the first time, a comprehensive investigation of these phenomena will become feasible on these little studied time scales. Due to the wide spectrum of relevant applications for 2D materials, I expect the outcome of AuDACE to have a crucial impact on the development of many key technological areas like optoelectronics, spintronics, valleytronics and photovoltaics.
Summary
Speed and performances of contemporary digital electronics are limited by the available device architectures and heat dissipation. Two-dimensional (2D) materials are emerging as one of the main candidates for designing new structures capable to overcome the current device limitations and foster the establishment of the electronics of the future. Due to the electron confinement in two directions, they are characterised by exotic physical, electronic and chemical properties, which are neither fully investigated nor understood. In particular, the lack of suitable tools hinders the possibility to study the ultrafast processes unfolding during light-matter interaction. Nevertheless, a clear understanding is required in order to leverage the unique properties of 2D materials. AuDACE aims to enter this unexplored region and investigate ultrafast electron, exciton and spin dynamics happening in advanced materials on time scales below few femtoseconds with unprecedented and ground-breaking possible outcome.
To reach this ambitious goal AuDACE will go beyond the state of the art and develop an innovative pump-probe beamline for transient absorption and reflectivity measurements based on arbitrarily polarised attosecond pulses in a two-foci geometry. Once the experimental techniques are established, my team and I will concentrate on ultrafast exciton dynamics in monolayer transition metal dichalcogenides (ML-TMDCs). In the final phase, AuDACE will focus on a new class of materials such as ferromagnetic ML-TMDCs to investigate the elusive physical mechanism responsible for ultrafast spin and magnetic dynamics. For the first time, a comprehensive investigation of these phenomena will become feasible on these little studied time scales. Due to the wide spectrum of relevant applications for 2D materials, I expect the outcome of AuDACE to have a crucial impact on the development of many key technological areas like optoelectronics, spintronics, valleytronics and photovoltaics.
Max ERC Funding
1 466 250 €
Duration
Start date: 2020-02-01, End date: 2025-01-31
Project acronym AXION
Project Axions: From Heaven to Earth
Researcher (PI) Frank Wilczek
Host Institution (HI) STOCKHOLMS UNIVERSITET
Country Sweden
Call Details Advanced Grant (AdG), PE2, ERC-2016-ADG
Summary Axions are hypothetical particles whose existence would solve two major problems: the strong P, T problem (a major blemish on the standard model); and the dark matter problem. It is a most important goal to either observe or rule out the existence of a cosmic axion background. It appears that decisive observations may be possible, but only after orchestrating insight from specialities ranging from quantum field theory and astrophysical modeling to ultra-low noise quantum measurement theory. Detailed predictions for the magnitude and structure of the cosmic axion background depend on cosmological and astrophysical modeling, which can be constrained by theoretical insight and numerical simulation. In parallel, we must optimize strategies for extracting accessible signals from that very weakly interacting source.
While the existence of axions as fundamental particles remains hypothetical, the equations governing how axions interact with electromagnetic fields also govern (with different parameters) how certain materials interact with electromagnetic fields. Thus those materials embody “emergent” axions. The equations have remarkable properties, which one can test in these materials, and possibly put to practical use.
Closely related to axions, mathematically, are anyons. Anyons are particle-like excitations that elude the familiar classification into bosons and fermions. Theoretical and numerical studies indicate that they are common emergent features of highly entangled states of matter in two dimensions. Recent work suggests the existence of states of matter, both natural and engineered, in which anyon dynamics is both important and experimentally accessible. Since the equations for anyons and axions are remarkably similar, and both have common, deep roots in symmetry and topology, it will be fruitful to consider them together.
Summary
Axions are hypothetical particles whose existence would solve two major problems: the strong P, T problem (a major blemish on the standard model); and the dark matter problem. It is a most important goal to either observe or rule out the existence of a cosmic axion background. It appears that decisive observations may be possible, but only after orchestrating insight from specialities ranging from quantum field theory and astrophysical modeling to ultra-low noise quantum measurement theory. Detailed predictions for the magnitude and structure of the cosmic axion background depend on cosmological and astrophysical modeling, which can be constrained by theoretical insight and numerical simulation. In parallel, we must optimize strategies for extracting accessible signals from that very weakly interacting source.
While the existence of axions as fundamental particles remains hypothetical, the equations governing how axions interact with electromagnetic fields also govern (with different parameters) how certain materials interact with electromagnetic fields. Thus those materials embody “emergent” axions. The equations have remarkable properties, which one can test in these materials, and possibly put to practical use.
Closely related to axions, mathematically, are anyons. Anyons are particle-like excitations that elude the familiar classification into bosons and fermions. Theoretical and numerical studies indicate that they are common emergent features of highly entangled states of matter in two dimensions. Recent work suggests the existence of states of matter, both natural and engineered, in which anyon dynamics is both important and experimentally accessible. Since the equations for anyons and axions are remarkably similar, and both have common, deep roots in symmetry and topology, it will be fruitful to consider them together.
Max ERC Funding
2 324 391 €
Duration
Start date: 2017-09-01, End date: 2022-08-31
Project acronym AxionDM
Project Searching for axion and axion-like-particle dark matter in the laboratory and with high-energy astrophysical observations
Researcher (PI) Manuel Meyer
Host Institution (HI) UNIVERSITAET HAMBURG
Country Germany
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary The nature of dark matter, which makes up more than 80% of the Universe's matter content, remains unknown. Light axions and axion-like particles (ALPs) are well motivated dark-matter candidates that could be detected through their oscillations into photons in the presence of magnetic fields. Here, complementary laboratory and astrophysical searches for dark-matter axions and ALPs are proposed that will cover more than 10 orders of magnitude of possible axion and ALP masses.
The astrophysical searches will focus on high-energy gamma-ray observations with the Fermi Large Area Telescope as well as current and future imaging air Cherenkov telescopes. Photon-ALP oscillations would cause features in the spectra of distant galaxies as well as gamma-ray bursts from core-collapse supernovae. Axion and ALP decay would also increase the opacity of the Universe for gamma rays. These signals will be searched for through novel comparisons of gamma-ray data and model predictions.
The laboratory searches will focus on contributions to the Any Light Particle Search (ALPS II) and International Axion Observatory (IAXO) experiments. New analysis and simulation frameworks, as well as trigger concepts, will be developed in order to significantly improve the background rejection for the Transition Edge Sensor (TES) detector employed in the ALPS experiment. These improvements could pave the way for an ALP detection in the laboratory with first data runs at the ALPS II experiment planned in 2021. Monte Carlo simulations will be used to assess whether TES detectors can achieve the low background rates required for IAXO. Such high energy resolution detectors could help to precisely measure the axion/ALP mass through mass-dependent spectral features.
Through an unprecedented investigation of axion and ALP signatures and by enhancing the sensitivity of future laboratory experiments, the proposed research will discover or rule out so-far unprobed dark-matter axions and ALPs.
Summary
The nature of dark matter, which makes up more than 80% of the Universe's matter content, remains unknown. Light axions and axion-like particles (ALPs) are well motivated dark-matter candidates that could be detected through their oscillations into photons in the presence of magnetic fields. Here, complementary laboratory and astrophysical searches for dark-matter axions and ALPs are proposed that will cover more than 10 orders of magnitude of possible axion and ALP masses.
The astrophysical searches will focus on high-energy gamma-ray observations with the Fermi Large Area Telescope as well as current and future imaging air Cherenkov telescopes. Photon-ALP oscillations would cause features in the spectra of distant galaxies as well as gamma-ray bursts from core-collapse supernovae. Axion and ALP decay would also increase the opacity of the Universe for gamma rays. These signals will be searched for through novel comparisons of gamma-ray data and model predictions.
The laboratory searches will focus on contributions to the Any Light Particle Search (ALPS II) and International Axion Observatory (IAXO) experiments. New analysis and simulation frameworks, as well as trigger concepts, will be developed in order to significantly improve the background rejection for the Transition Edge Sensor (TES) detector employed in the ALPS experiment. These improvements could pave the way for an ALP detection in the laboratory with first data runs at the ALPS II experiment planned in 2021. Monte Carlo simulations will be used to assess whether TES detectors can achieve the low background rates required for IAXO. Such high energy resolution detectors could help to precisely measure the axion/ALP mass through mass-dependent spectral features.
Through an unprecedented investigation of axion and ALP signatures and by enhancing the sensitivity of future laboratory experiments, the proposed research will discover or rule out so-far unprobed dark-matter axions and ALPs.
Max ERC Funding
1 440 763 €
Duration
Start date: 2021-06-01, End date: 2026-05-31
