Project acronym 2F4BIODYN
Project Two-Field Nuclear Magnetic Resonance Spectroscopy for the Exploration of Biomolecular Dynamics
Researcher (PI) Fabien Ferrage
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2011-StG_20101014
Summary The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Summary
The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Max ERC Funding
1 462 080 €
Duration
Start date: 2012-01-01, End date: 2017-12-31
Project acronym 3D-BioMat
Project Deciphering biomineralization mechanisms through 3D explorations of mesoscale crystalline structure in calcareous biomaterials
Researcher (PI) VIRGINIE CHAMARD
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Consolidator Grant (CoG), PE3, ERC-2016-COG
Summary The fundamental 3D-BioMat project aims at providing a biomineralization model to explain the formation of microscopic calcareous single-crystals produced by living organisms. Although these crystals present a wide variety of shapes, associated to various organic materials, the observation of a nanoscale granular structure common to almost all calcareous crystallizing organisms, associated to an extended crystalline coherence, underlies a generic biomineralization and assembly process. A key to building realistic scenarios of biomineralization is to reveal the crystalline architecture, at the mesoscale, (i. e., over a few granules), which none of the existing nano-characterization tools is able to provide.
3D-BioMat is based on the recognized PI’s expertise in the field of synchrotron coherent x-ray diffraction microscopy. It will extend the PI’s disruptive pioneering microscopy formalism, towards an innovative high-throughput approach able at giving access to the 3D mesoscale image of the crystalline properties (crystal-line coherence, crystal plane tilts and strains) with the required flexibility, nanoscale resolution, and non-invasiveness.
This achievement will be used to timely reveal the generics of the mesoscale crystalline structure through the pioneering explorations of a vast variety of crystalline biominerals produced by the famous Pinctada mar-garitifera oyster shell, and thereby build a realistic biomineralization scenario.
The inferred biomineralization pathways, including both physico-chemical pathways and biological controls, will ultimately be validated by comparing the mesoscale structures produced by biomimetic samples with the biogenic ones. Beyond deciphering one of the most intriguing questions of material nanosciences, 3D-BioMat may contribute to new climate models, pave the way for new routes in material synthesis and supply answers to the pearl-culture calcification problems.
Summary
The fundamental 3D-BioMat project aims at providing a biomineralization model to explain the formation of microscopic calcareous single-crystals produced by living organisms. Although these crystals present a wide variety of shapes, associated to various organic materials, the observation of a nanoscale granular structure common to almost all calcareous crystallizing organisms, associated to an extended crystalline coherence, underlies a generic biomineralization and assembly process. A key to building realistic scenarios of biomineralization is to reveal the crystalline architecture, at the mesoscale, (i. e., over a few granules), which none of the existing nano-characterization tools is able to provide.
3D-BioMat is based on the recognized PI’s expertise in the field of synchrotron coherent x-ray diffraction microscopy. It will extend the PI’s disruptive pioneering microscopy formalism, towards an innovative high-throughput approach able at giving access to the 3D mesoscale image of the crystalline properties (crystal-line coherence, crystal plane tilts and strains) with the required flexibility, nanoscale resolution, and non-invasiveness.
This achievement will be used to timely reveal the generics of the mesoscale crystalline structure through the pioneering explorations of a vast variety of crystalline biominerals produced by the famous Pinctada mar-garitifera oyster shell, and thereby build a realistic biomineralization scenario.
The inferred biomineralization pathways, including both physico-chemical pathways and biological controls, will ultimately be validated by comparing the mesoscale structures produced by biomimetic samples with the biogenic ones. Beyond deciphering one of the most intriguing questions of material nanosciences, 3D-BioMat may contribute to new climate models, pave the way for new routes in material synthesis and supply answers to the pearl-culture calcification problems.
Max ERC Funding
1 966 429 €
Duration
Start date: 2017-03-01, End date: 2022-02-28
Project acronym A-LIFE
Project The asymmetry of life: towards a unified view of the emergence of biological homochirality
Researcher (PI) Cornelia MEINERT
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2018-STG
Summary What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Summary
What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Max ERC Funding
1 500 000 €
Duration
Start date: 2019-04-01, End date: 2024-03-31
Project acronym ABACUS
Project Advancing Behavioral and Cognitive Understanding of Speech
Researcher (PI) Bart De Boer
Host Institution (HI) VRIJE UNIVERSITEIT BRUSSEL
Call Details Starting Grant (StG), SH4, ERC-2011-StG_20101124
Summary I intend to investigate what cognitive mechanisms give us combinatorial speech. Combinatorial speech is the ability to make new words using pre-existing speech sounds. Humans are the only apes that can do this, yet we do not know how our brains do it, nor how exactly we differ from other apes. Using new experimental techniques to study human behavior and new computational techniques to model human cognition, I will find out how we deal with combinatorial speech.
The experimental part will study individual and cultural learning. Experimental cultural learning is a new technique that simulates cultural evolution in the laboratory. Two types of cultural learning will be used: iterated learning, which simulates language transfer across generations, and social coordination, which simulates emergence of norms in a language community. Using the two types of cultural learning together with individual learning experiments will help to zero in, from three angles, on how humans deal with combinatorial speech. In addition it will make a methodological contribution by comparing the strengths and weaknesses of the three methods.
The computer modeling part will formalize hypotheses about how our brains deal with combinatorial speech. Two models will be built: a high-level model that will establish the basic algorithms with which combinatorial speech is learned and reproduced, and a neural model that will establish in more detail how the algorithms are implemented in the brain. In addition, the models, through increasing understanding of how humans deal with speech, will help bridge the performance gap between human and computer speech recognition.
The project will advance science in four ways: it will provide insight into how our unique ability for using combinatorial speech works, it will tell us how this is implemented in the brain, it will extend the novel methodology of experimental cultural learning and it will create new computer models for dealing with human speech.
Summary
I intend to investigate what cognitive mechanisms give us combinatorial speech. Combinatorial speech is the ability to make new words using pre-existing speech sounds. Humans are the only apes that can do this, yet we do not know how our brains do it, nor how exactly we differ from other apes. Using new experimental techniques to study human behavior and new computational techniques to model human cognition, I will find out how we deal with combinatorial speech.
The experimental part will study individual and cultural learning. Experimental cultural learning is a new technique that simulates cultural evolution in the laboratory. Two types of cultural learning will be used: iterated learning, which simulates language transfer across generations, and social coordination, which simulates emergence of norms in a language community. Using the two types of cultural learning together with individual learning experiments will help to zero in, from three angles, on how humans deal with combinatorial speech. In addition it will make a methodological contribution by comparing the strengths and weaknesses of the three methods.
The computer modeling part will formalize hypotheses about how our brains deal with combinatorial speech. Two models will be built: a high-level model that will establish the basic algorithms with which combinatorial speech is learned and reproduced, and a neural model that will establish in more detail how the algorithms are implemented in the brain. In addition, the models, through increasing understanding of how humans deal with speech, will help bridge the performance gap between human and computer speech recognition.
The project will advance science in four ways: it will provide insight into how our unique ability for using combinatorial speech works, it will tell us how this is implemented in the brain, it will extend the novel methodology of experimental cultural learning and it will create new computer models for dealing with human speech.
Max ERC Funding
1 276 620 €
Duration
Start date: 2012-02-01, End date: 2017-01-31
Project acronym ABIOS
Project ABIOtic Synthesis of RNA: an investigation on how life started before biology existed
Researcher (PI) Guillaume STIRNEMANN
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2017-STG
Summary The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Summary
The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Max ERC Funding
1 497 031 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym ADAM
Project The Adaptive Auditory Mind
Researcher (PI) Shihab Shamma
Host Institution (HI) ECOLE NORMALE SUPERIEURE
Call Details Advanced Grant (AdG), SH4, ERC-2011-ADG_20110406
Summary Listening in realistic situations is an active process that engages perceptual and cognitive faculties, endowing speech with meaning, music with joy, and environmental sounds with emotion. Through hearing, humans and other animals navigate complex acoustic scenes, separate sound mixtures, and assess their behavioral relevance. These remarkable feats are currently beyond our understanding and exceed the capabilities of the most sophisticated audio engineering systems. The goal of the proposed research is to investigate experimentally a novel view of hearing, where active hearing emerges from a deep interplay between adaptive sensory processes and goal-directed cognition. Specifically, we shall explore the postulate that versatile perception is mediated by rapid-plasticity at the neuronal level. At the conjunction of sensory and cognitive processing, rapid-plasticity pervades all levels of auditory system, from the cochlea up to the auditory and prefrontal cortices. Exploiting fundamental statistical regularities of acoustics, it is what allows humans and other animal to deal so successfully with natural acoustic scenes where artificial systems fail. The project builds on the internationally recognized leadership of the PI in the fields of physiology and computational modeling, combined with the expertise of the Co-Investigator in psychophysics. Building on these highly complementary fields and several technical innovations, we hope to promote a novel view of auditory perception and cognition. We aim also to contribute significantly to translational research in the domain of signal processing for clinical hearing aids, given that many current limitations are not technological but rather conceptual. The project will finally result in the creation of laboratory facilities and an intellectual network unique in France and rare in all of Europe, combining cognitive, neural, and computational approaches to auditory neuroscience.
Summary
Listening in realistic situations is an active process that engages perceptual and cognitive faculties, endowing speech with meaning, music with joy, and environmental sounds with emotion. Through hearing, humans and other animals navigate complex acoustic scenes, separate sound mixtures, and assess their behavioral relevance. These remarkable feats are currently beyond our understanding and exceed the capabilities of the most sophisticated audio engineering systems. The goal of the proposed research is to investigate experimentally a novel view of hearing, where active hearing emerges from a deep interplay between adaptive sensory processes and goal-directed cognition. Specifically, we shall explore the postulate that versatile perception is mediated by rapid-plasticity at the neuronal level. At the conjunction of sensory and cognitive processing, rapid-plasticity pervades all levels of auditory system, from the cochlea up to the auditory and prefrontal cortices. Exploiting fundamental statistical regularities of acoustics, it is what allows humans and other animal to deal so successfully with natural acoustic scenes where artificial systems fail. The project builds on the internationally recognized leadership of the PI in the fields of physiology and computational modeling, combined with the expertise of the Co-Investigator in psychophysics. Building on these highly complementary fields and several technical innovations, we hope to promote a novel view of auditory perception and cognition. We aim also to contribute significantly to translational research in the domain of signal processing for clinical hearing aids, given that many current limitations are not technological but rather conceptual. The project will finally result in the creation of laboratory facilities and an intellectual network unique in France and rare in all of Europe, combining cognitive, neural, and computational approaches to auditory neuroscience.
Max ERC Funding
3 199 078 €
Duration
Start date: 2012-10-01, End date: 2018-09-30
Project acronym ADEQUATE
Project Advanced optoelectronic Devices with Enhanced QUAntum efficiency at THz frEquencies
Researcher (PI) Carlo Sirtori
Host Institution (HI) UNIVERSITE PARIS DIDEROT - PARIS 7
Call Details Advanced Grant (AdG), PE3, ERC-2009-AdG
Summary The aim of this project is the realisation of efficient mid-infrared and THz optoelectronic emitters. This work is motivated by the fact that the spontaneous emission in this frequency range is characterized by an extremely long lifetime when compared to non-radiative processes, giving rise to devices with very low quantum efficiency. To this end we want to develop hybrid light-matter systems, already well known in quantum optics, within optoelectronics devices, that will be driven by electrical injection. With this project we want to extend the field of optoelectronics by introducing some of the concepts of quantum optic, particularly the light-matter strong coupling, into semiconductor devices. More precisely this project aims at the implementation of novel optoelectronic emitters operating in the strong coupling regime between an intersubband excitation of a two-dimensional electron gas and a microcavity photonic mode. The quasiparticles issued from this coupling are called intersubband polaritons. The major difficulties and challenges of this project, do not lay in the observation of these quantum effects, but in their exploitation for a specific function, in particular an efficient electrical to optical conversion. To obtain efficient quantum emitters in the THz frequency range we will follow two different approaches: - In the first case we will try to exploit the additional characteristic time of the system introduced by the light-matter interaction in the strong (or ultra-strong) coupling regime. - The second approach will exploit the fact that, under certain conditions, intersubband polaritons have a bosonic character; as a consequence they can undergo stimulated scattering, giving rise to polaritons lasers as it has been shown for excitonic polaritons.
Summary
The aim of this project is the realisation of efficient mid-infrared and THz optoelectronic emitters. This work is motivated by the fact that the spontaneous emission in this frequency range is characterized by an extremely long lifetime when compared to non-radiative processes, giving rise to devices with very low quantum efficiency. To this end we want to develop hybrid light-matter systems, already well known in quantum optics, within optoelectronics devices, that will be driven by electrical injection. With this project we want to extend the field of optoelectronics by introducing some of the concepts of quantum optic, particularly the light-matter strong coupling, into semiconductor devices. More precisely this project aims at the implementation of novel optoelectronic emitters operating in the strong coupling regime between an intersubband excitation of a two-dimensional electron gas and a microcavity photonic mode. The quasiparticles issued from this coupling are called intersubband polaritons. The major difficulties and challenges of this project, do not lay in the observation of these quantum effects, but in their exploitation for a specific function, in particular an efficient electrical to optical conversion. To obtain efficient quantum emitters in the THz frequency range we will follow two different approaches: - In the first case we will try to exploit the additional characteristic time of the system introduced by the light-matter interaction in the strong (or ultra-strong) coupling regime. - The second approach will exploit the fact that, under certain conditions, intersubband polaritons have a bosonic character; as a consequence they can undergo stimulated scattering, giving rise to polaritons lasers as it has been shown for excitonic polaritons.
Max ERC Funding
1 761 000 €
Duration
Start date: 2010-05-01, End date: 2015-04-30
Project acronym AMPERE
Project Accounting for Metallicity, Polarization of the Electrolyte, and Redox reactions in computational Electrochemistry
Researcher (PI) Mathieu Eric Salanne
Host Institution (HI) SORBONNE UNIVERSITE
Call Details Consolidator Grant (CoG), PE4, ERC-2017-COG
Summary Applied electrochemistry plays a key role in many technologies, such as batteries, fuel cells, supercapacitors or solar cells. It is therefore at the core of many research programs all over the world. Yet, fundamental electrochemical investigations remain scarce. In particular, electrochemistry is among the fields for which the gap between theory and experiment is the largest. From the computational point of view, there is no molecular dynamics (MD) software devoted to the simulation of electrochemical systems while other fields such as biochemistry (GROMACS) or material science (LAMMPS) have dedicated tools. This is due to the difficulty of accounting for complex effects arising from (i) the degree of metallicity of the electrode (i.e. from semimetals to perfect conductors), (ii) the mutual polarization occurring at the electrode/electrolyte interface and (iii) the redox reactivity through explicit electron transfers. Current understanding therefore relies on standard theories that derive from an inaccurate molecular-scale picture. My objective is to fill this gap by introducing a whole set of new methods for simulating electrochemical systems. They will be provided to the computational electrochemistry community as a cutting-edge MD software adapted to supercomputers. First applications will aim at the discovery of new electrolytes for energy storage. Here I will focus on (1) ‘‘water-in-salts’’ to understand why these revolutionary liquids enable much higher voltage than conventional solutions (2) redox reactions inside a nanoporous electrode to support the development of future capacitive energy storage devices. These selected applications are timely and rely on collaborations with leading experimental partners. The results are expected to shed an unprecedented light on the importance of polarization effects on the structure and the reactivity of electrode/electrolyte interfaces, establishing MD as a prominent tool for solving complex electrochemistry problems.
Summary
Applied electrochemistry plays a key role in many technologies, such as batteries, fuel cells, supercapacitors or solar cells. It is therefore at the core of many research programs all over the world. Yet, fundamental electrochemical investigations remain scarce. In particular, electrochemistry is among the fields for which the gap between theory and experiment is the largest. From the computational point of view, there is no molecular dynamics (MD) software devoted to the simulation of electrochemical systems while other fields such as biochemistry (GROMACS) or material science (LAMMPS) have dedicated tools. This is due to the difficulty of accounting for complex effects arising from (i) the degree of metallicity of the electrode (i.e. from semimetals to perfect conductors), (ii) the mutual polarization occurring at the electrode/electrolyte interface and (iii) the redox reactivity through explicit electron transfers. Current understanding therefore relies on standard theories that derive from an inaccurate molecular-scale picture. My objective is to fill this gap by introducing a whole set of new methods for simulating electrochemical systems. They will be provided to the computational electrochemistry community as a cutting-edge MD software adapted to supercomputers. First applications will aim at the discovery of new electrolytes for energy storage. Here I will focus on (1) ‘‘water-in-salts’’ to understand why these revolutionary liquids enable much higher voltage than conventional solutions (2) redox reactions inside a nanoporous electrode to support the development of future capacitive energy storage devices. These selected applications are timely and rely on collaborations with leading experimental partners. The results are expected to shed an unprecedented light on the importance of polarization effects on the structure and the reactivity of electrode/electrolyte interfaces, establishing MD as a prominent tool for solving complex electrochemistry problems.
Max ERC Funding
1 588 769 €
Duration
Start date: 2018-04-01, End date: 2023-03-31
Project acronym APOGEE
Project Atomic-scale physics of single-photon sources.
Researcher (PI) GUILLAUME ARTHUR FRANCOIS SCHULL
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Consolidator Grant (CoG), PE3, ERC-2017-COG
Summary Single-photon sources (SPSs) are systems capable of emitting photons one by one. These sources are of major importance for quantum-information science and applications. SPSs experiments generally rely on the optical excitation of two level systems of atomic-scale dimensions (single-molecules, vacancies in diamond…). Many fundamental questions related to the nature of these sources and the impact of their environment remain to be explored:
Can SPSs be addressed with atomic-scale spatial accuracy? How do the nanometer-scale distance or the orientation between two (or more) SPSs affect their emission properties? Does coherence emerge from the proximity between the sources? Do these structures still behave as SPSs or do they lead to the emission of correlated photons? How can we then control the degree of entanglement between the sources? Can we remotely excite the emission of these sources by using molecular chains as charge-carrying wires? Can we couple SPSs embodied in one or two-dimensional arrays? How does mechanical stress or localised plasmons affect the properties of an electrically-driven SPS?
Answering these questions requires probing, manipulating and exciting SPSs with an atomic-scale precision. This is beyond what is attainable with an all-optical method. Since they can be confined to atomic-scale pathways we propose to use electrons rather than photons to excite the SPSs. This unconventional approach provides a direct access to the atomic-scale physics of SPSs and is relevant for the implementation of these sources in hybrid devices combining electronic and photonic components. To this end, a scanning probe microscope will be developed that provides simultaneous spatial, chemical, spectral, and temporal resolutions. Single-molecules and defects in monolayer transition metal dichalcogenides are SPSs that will be studied in the project, and which are respectively of interest for fundamental and more applied issues.
Summary
Single-photon sources (SPSs) are systems capable of emitting photons one by one. These sources are of major importance for quantum-information science and applications. SPSs experiments generally rely on the optical excitation of two level systems of atomic-scale dimensions (single-molecules, vacancies in diamond…). Many fundamental questions related to the nature of these sources and the impact of their environment remain to be explored:
Can SPSs be addressed with atomic-scale spatial accuracy? How do the nanometer-scale distance or the orientation between two (or more) SPSs affect their emission properties? Does coherence emerge from the proximity between the sources? Do these structures still behave as SPSs or do they lead to the emission of correlated photons? How can we then control the degree of entanglement between the sources? Can we remotely excite the emission of these sources by using molecular chains as charge-carrying wires? Can we couple SPSs embodied in one or two-dimensional arrays? How does mechanical stress or localised plasmons affect the properties of an electrically-driven SPS?
Answering these questions requires probing, manipulating and exciting SPSs with an atomic-scale precision. This is beyond what is attainable with an all-optical method. Since they can be confined to atomic-scale pathways we propose to use electrons rather than photons to excite the SPSs. This unconventional approach provides a direct access to the atomic-scale physics of SPSs and is relevant for the implementation of these sources in hybrid devices combining electronic and photonic components. To this end, a scanning probe microscope will be developed that provides simultaneous spatial, chemical, spectral, and temporal resolutions. Single-molecules and defects in monolayer transition metal dichalcogenides are SPSs that will be studied in the project, and which are respectively of interest for fundamental and more applied issues.
Max ERC Funding
1 996 848 €
Duration
Start date: 2018-06-01, End date: 2023-05-31
Project acronym AQUARAMAN
Project Pipet Based Scanning Probe Microscopy Tip-Enhanced Raman Spectroscopy: A Novel Approach for TERS in Liquids
Researcher (PI) Aleix Garcia Guell
Host Institution (HI) ECOLE POLYTECHNIQUE
Call Details Starting Grant (StG), PE4, ERC-2016-STG
Summary Tip-enhanced Raman spectroscopy (TERS) is often described as the most powerful tool for optical characterization of surfaces and their proximities. It combines the intrinsic spatial resolution of scanning probe techniques (AFM or STM) with the chemical information content of vibrational Raman spectroscopy. Capable to reveal surface heterogeneity at the nanoscale, TERS is currently playing a fundamental role in the understanding of interfacial physicochemical processes in key areas of science and technology such as chemistry, biology and material science.
Unfortunately, the undeniable potential of TERS as a label-free tool for nanoscale chemical and structural characterization is, nowadays, limited to air and vacuum environments, with it failing to operate in a reliable and systematic manner in liquid. The reasons are more technical than fundamental, as what is hindering the application of TERS in water is, among other issues, the low stability of the probes and their consistency. Fields of science and technology where the presence of water/electrolyte is unavoidable, such as biology and electrochemistry, remain unexplored with this powerful technique.
We propose a revolutionary approach for TERS in liquids founded on the employment of pipet-based scanning probe microscopy techniques (pb-SPM) as an alternative to AFM and STM. The use of recent but well established pb-SPM brings the opportunity to develop unprecedented pipet-based TERS probes (beyond the classic and limited metallized solid probes from AFM and STM), together with the implementation of ingenious and innovative measures to enhance tip stability, sensitivity and reliability, unattainable with the current techniques.
We will be in possession of a unique nano-spectroscopy platform capable of experiments in liquids, to follow dynamic processes in-situ, addressing fundamental questions and bringing insight into interfacial phenomena spanning from materials science, physics, chemistry and biology.
Summary
Tip-enhanced Raman spectroscopy (TERS) is often described as the most powerful tool for optical characterization of surfaces and their proximities. It combines the intrinsic spatial resolution of scanning probe techniques (AFM or STM) with the chemical information content of vibrational Raman spectroscopy. Capable to reveal surface heterogeneity at the nanoscale, TERS is currently playing a fundamental role in the understanding of interfacial physicochemical processes in key areas of science and technology such as chemistry, biology and material science.
Unfortunately, the undeniable potential of TERS as a label-free tool for nanoscale chemical and structural characterization is, nowadays, limited to air and vacuum environments, with it failing to operate in a reliable and systematic manner in liquid. The reasons are more technical than fundamental, as what is hindering the application of TERS in water is, among other issues, the low stability of the probes and their consistency. Fields of science and technology where the presence of water/electrolyte is unavoidable, such as biology and electrochemistry, remain unexplored with this powerful technique.
We propose a revolutionary approach for TERS in liquids founded on the employment of pipet-based scanning probe microscopy techniques (pb-SPM) as an alternative to AFM and STM. The use of recent but well established pb-SPM brings the opportunity to develop unprecedented pipet-based TERS probes (beyond the classic and limited metallized solid probes from AFM and STM), together with the implementation of ingenious and innovative measures to enhance tip stability, sensitivity and reliability, unattainable with the current techniques.
We will be in possession of a unique nano-spectroscopy platform capable of experiments in liquids, to follow dynamic processes in-situ, addressing fundamental questions and bringing insight into interfacial phenomena spanning from materials science, physics, chemistry and biology.
Max ERC Funding
1 528 442 €
Duration
Start date: 2017-07-01, End date: 2022-06-30