Project acronym AFRIVAL
Project African river basins: catchment-scale carbon fluxes and transformations
Researcher (PI) Steven Bouillon
Host Institution (HI) KATHOLIEKE UNIVERSITEIT LEUVEN
Country Belgium
Call Details Starting Grant (StG), PE10, ERC-2009-StG
Summary This proposal wishes to fundamentally improve our understanding of the role of tropical freshwater ecosystems in carbon (C) cycling on the catchment scale. It uses an unprecedented combination of state-of-the-art proxies such as stable isotope, 14C and biomarker signatures to characterize organic matter, radiogenic isotope signatures to determine particle residence times, as well as field measurements of relevant biogeochemical processes. We focus on tropical systems since there is a striking lack of data on such systems, even though riverine C transport is thought to be disproportionately high in tropical areas. Furthermore, the presence of landscape-scale contrasts in vegetation (in particular, C3 vs. C4 plants) are an important asset in the use of stable isotopes as natural tracers of C cycling processes on this scale. Freshwater ecosystems are an important component in the global C cycle, and the primary link between terrestrial and marine ecosystems. Recent estimates indicate that ~2 Pg C y-1 (Pg=Petagram) enter freshwater systems, i.e., about twice the estimated global terrestrial C sink. More than half of this is thought to be remineralized before it reaches the coastal zone, and for the Amazon basin this has even been suggested to be ~90% of the lateral C inputs. The question how general these patterns are is a matter of debate, and assessing the mechanisms determining the degree of processing versus transport of organic carbon in lakes and river systems is critical to further constrain their role in the global C cycle. This proposal provides an interdisciplinary approach to describe and quantify catchment-scale C transport and cycling in tropical river basins. Besides conceptual and methodological advances, and a significant expansion of our dataset on C processes in such systems, new data gathered in this project are likely to provide exciting and novel hypotheses on the functioning of freshwater systems and their linkage to the terrestrial C budget.
Summary
This proposal wishes to fundamentally improve our understanding of the role of tropical freshwater ecosystems in carbon (C) cycling on the catchment scale. It uses an unprecedented combination of state-of-the-art proxies such as stable isotope, 14C and biomarker signatures to characterize organic matter, radiogenic isotope signatures to determine particle residence times, as well as field measurements of relevant biogeochemical processes. We focus on tropical systems since there is a striking lack of data on such systems, even though riverine C transport is thought to be disproportionately high in tropical areas. Furthermore, the presence of landscape-scale contrasts in vegetation (in particular, C3 vs. C4 plants) are an important asset in the use of stable isotopes as natural tracers of C cycling processes on this scale. Freshwater ecosystems are an important component in the global C cycle, and the primary link between terrestrial and marine ecosystems. Recent estimates indicate that ~2 Pg C y-1 (Pg=Petagram) enter freshwater systems, i.e., about twice the estimated global terrestrial C sink. More than half of this is thought to be remineralized before it reaches the coastal zone, and for the Amazon basin this has even been suggested to be ~90% of the lateral C inputs. The question how general these patterns are is a matter of debate, and assessing the mechanisms determining the degree of processing versus transport of organic carbon in lakes and river systems is critical to further constrain their role in the global C cycle. This proposal provides an interdisciplinary approach to describe and quantify catchment-scale C transport and cycling in tropical river basins. Besides conceptual and methodological advances, and a significant expansion of our dataset on C processes in such systems, new data gathered in this project are likely to provide exciting and novel hypotheses on the functioning of freshwater systems and their linkage to the terrestrial C budget.
Max ERC Funding
1 745 262 €
Duration
Start date: 2009-10-01, End date: 2014-09-30
Project acronym AIM2 INFLAMMASOME
Project Cytosolic recognition of foreign nucleic acids: Molecular and functional characterization of AIM2, a central player in DNA-triggered inflammasome activation
Researcher (PI) Veit Hornung
Host Institution (HI) UNIVERSITATSKLINIKUM BONN
Country Germany
Call Details Starting Grant (StG), LS6, ERC-2009-StG
Summary Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Summary
Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Max ERC Funding
1 727 920 €
Duration
Start date: 2009-12-01, End date: 2014-11-30
Project acronym ALIGN
Project Ab-initio computational modelling of photovoltaic interfaces
Researcher (PI) Feliciano Giustino
Host Institution (HI) THE CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD
Country United Kingdom
Call Details Starting Grant (StG), PE5, ERC-2009-StG
Summary The aim of the ALIGN project is to understand, predict, and optimize the photovoltaic energy conversion in third-generation solar cells, starting from an atomic-scale quantum-mechanical modelling of the photovoltaic interface. The quest for photovoltaic materials suitable for low-cost synthesis, large-area production, and functional architecture has driven substantial research efforts towards third-generation photovoltaic devices such as plastic solar cells, organic-inorganic cells, and photo-electrochemical cells. The physical and chemical processes involved in the harvesting of sunlight, the transport of electrical charge, and the build-up of the photo-voltage in these devices are fundamentally different from those encountered in traditional semiconductor heterojunction solar cells. A detailed atomic-scale quantum-mechanical description of such processes will lay down the basis for a rational approach to the modelling, optimization, and design of new photovoltaic materials. The short name of the proposal hints at one of the key materials parameters in the area of photovoltaic interfaces: the alignment of the quantum energy levels between the light-absorbing material and the electron acceptor. The level alignment drives the separation of the electron-hole pairs formed upon absorption of sunlight, and determines the open circuit voltage of the solar cell. The energy level alignment not only represents a key parameter for the design of photovoltaic devices, but also constitutes one of the grand challenges of modern computational materials science. Within this project we will develop and apply new ground-breaking computational methods to understand, predict, and optimize the energy level alignment and other design parameters of third-generation photovoltaic devices.
Summary
The aim of the ALIGN project is to understand, predict, and optimize the photovoltaic energy conversion in third-generation solar cells, starting from an atomic-scale quantum-mechanical modelling of the photovoltaic interface. The quest for photovoltaic materials suitable for low-cost synthesis, large-area production, and functional architecture has driven substantial research efforts towards third-generation photovoltaic devices such as plastic solar cells, organic-inorganic cells, and photo-electrochemical cells. The physical and chemical processes involved in the harvesting of sunlight, the transport of electrical charge, and the build-up of the photo-voltage in these devices are fundamentally different from those encountered in traditional semiconductor heterojunction solar cells. A detailed atomic-scale quantum-mechanical description of such processes will lay down the basis for a rational approach to the modelling, optimization, and design of new photovoltaic materials. The short name of the proposal hints at one of the key materials parameters in the area of photovoltaic interfaces: the alignment of the quantum energy levels between the light-absorbing material and the electron acceptor. The level alignment drives the separation of the electron-hole pairs formed upon absorption of sunlight, and determines the open circuit voltage of the solar cell. The energy level alignment not only represents a key parameter for the design of photovoltaic devices, but also constitutes one of the grand challenges of modern computational materials science. Within this project we will develop and apply new ground-breaking computational methods to understand, predict, and optimize the energy level alignment and other design parameters of third-generation photovoltaic devices.
Max ERC Funding
1 000 000 €
Duration
Start date: 2010-03-01, End date: 2016-02-29
Project acronym ANSR
Project Ab initio approach to nuclear structure and reactions (++)
Researcher (PI) Christian Erik Forssen
Host Institution (HI) CHALMERS TEKNISKA HOEGSKOLA AB
Country Sweden
Call Details Starting Grant (StG), PE2, ERC-2009-StG
Summary Today, much interest in several fields of physics is devoted to the study of small, open quantum systems, whose properties are profoundly affected by the environment; i.e., the continuum of decay channels. In nuclear physics, these problems were originally studied in the context of nuclear reactions but their importance has been reestablished with the advent of radioactive-beam physics and the resulting interest in exotic nuclei. In particular, strong theory initiatives in this area of research will be instrumental for the success of the experimental program at the Facility for Antiproton and Ion Research (FAIR) in Germany. In addition, many of the aspects of open quantum systems are also being explored in the rapidly evolving research on ultracold atomic gases, quantum dots, and other nanodevices. A first-principles description of open quantum systems presents a substantial theoretical and computational challenge. However, the current availability of enormous computing power has allowed theorists to make spectacular progress on problems that were previously thought intractable. The importance of computational methods to study quantum many-body systems is stressed in this proposal. Our approach is based on the ab initio no-core shell model (NCSM), which is a well-established theoretical framework aimed originally at an exact description of nuclear structure starting from realistic inter-nucleon forces. A successful completion of this project requires extensions of the NCSM mathematical framework and the development of highly advanced computer codes. The '++' in the project title indicates the interdisciplinary aspects of the present research proposal and the ambition to make a significant impact on connected fields of many-body physics.
Summary
Today, much interest in several fields of physics is devoted to the study of small, open quantum systems, whose properties are profoundly affected by the environment; i.e., the continuum of decay channels. In nuclear physics, these problems were originally studied in the context of nuclear reactions but their importance has been reestablished with the advent of radioactive-beam physics and the resulting interest in exotic nuclei. In particular, strong theory initiatives in this area of research will be instrumental for the success of the experimental program at the Facility for Antiproton and Ion Research (FAIR) in Germany. In addition, many of the aspects of open quantum systems are also being explored in the rapidly evolving research on ultracold atomic gases, quantum dots, and other nanodevices. A first-principles description of open quantum systems presents a substantial theoretical and computational challenge. However, the current availability of enormous computing power has allowed theorists to make spectacular progress on problems that were previously thought intractable. The importance of computational methods to study quantum many-body systems is stressed in this proposal. Our approach is based on the ab initio no-core shell model (NCSM), which is a well-established theoretical framework aimed originally at an exact description of nuclear structure starting from realistic inter-nucleon forces. A successful completion of this project requires extensions of the NCSM mathematical framework and the development of highly advanced computer codes. The '++' in the project title indicates the interdisciplinary aspects of the present research proposal and the ambition to make a significant impact on connected fields of many-body physics.
Max ERC Funding
1 304 800 €
Duration
Start date: 2009-12-01, End date: 2014-11-30
Project acronym ANTIVIRALRNAI
Project RNAi-mediated viral immunity in insects
Researcher (PI) Maria-Carla Saleh
Host Institution (HI) INSTITUT PASTEUR
Country France
Call Details Starting Grant (StG), LS6, ERC-2009-StG
Summary RNA interference (RNAi) is a conserved sequence-specific, gene-silencing mechanism that is induced by double-stranded RNA (dsRNA). One of the functions of this pathway is the defense against parasitic nucleic acids: transposons and viruses. Previous results demonstrated that viral infections in Drosophila melanogaster are fought by an antiviral RNAi response and that components of the endocytic pathway are required for dsRNA entry to initiate the RNAi response. Recently we have shown that infected insect cells spread a systemic silencing signal that elicits a protective RNAi-dependent immunity throughout the organism. This suggests that the cell-autonomous RNAi response is insufficient to control a viral infection and that flies also rely on systemic immune response to fight against such infections. As a junior group leader, I will study the mechanisms that mediate the RNAi-based antiviral response in insects. By combining biochemical, cellular, molecular and genomic approaches, both in vivo and in cell culture, I will analyze the mechanisms underlying viral tropism, systemic propagation of the antiviral signal and the basis of the persistence of the antiviral state. Furthermore, I will examine whether the dsRNA-uptake pathway is conserved in mosquitoes and its relationship with viral immunity in that host. This comprehensive approach will tackle how this nucleic acid-based immunity works in insects to generate an anti-viral stage. A better understanding of the role of RNA silencing in insects during virus infection will allow the exploitation of this pathway for improvement of public health related problems such as arbovirus infection and disease.
Summary
RNA interference (RNAi) is a conserved sequence-specific, gene-silencing mechanism that is induced by double-stranded RNA (dsRNA). One of the functions of this pathway is the defense against parasitic nucleic acids: transposons and viruses. Previous results demonstrated that viral infections in Drosophila melanogaster are fought by an antiviral RNAi response and that components of the endocytic pathway are required for dsRNA entry to initiate the RNAi response. Recently we have shown that infected insect cells spread a systemic silencing signal that elicits a protective RNAi-dependent immunity throughout the organism. This suggests that the cell-autonomous RNAi response is insufficient to control a viral infection and that flies also rely on systemic immune response to fight against such infections. As a junior group leader, I will study the mechanisms that mediate the RNAi-based antiviral response in insects. By combining biochemical, cellular, molecular and genomic approaches, both in vivo and in cell culture, I will analyze the mechanisms underlying viral tropism, systemic propagation of the antiviral signal and the basis of the persistence of the antiviral state. Furthermore, I will examine whether the dsRNA-uptake pathway is conserved in mosquitoes and its relationship with viral immunity in that host. This comprehensive approach will tackle how this nucleic acid-based immunity works in insects to generate an anti-viral stage. A better understanding of the role of RNA silencing in insects during virus infection will allow the exploitation of this pathway for improvement of public health related problems such as arbovirus infection and disease.
Max ERC Funding
1 900 000 €
Duration
Start date: 2009-10-01, End date: 2014-12-31
Project acronym ARCHGLASS
Project Archaeometry and Archaeology of Ancient Glass Production as a Source for Ancient Technology and Trade of Raw Materials
Researcher (PI) Patrick Degryse
Host Institution (HI) KATHOLIEKE UNIVERSITEIT LEUVEN
Country Belgium
Call Details Starting Grant (StG), SH6, ERC-2009-StG
Summary In this project, innovative techniques to reconstruct ancient economies are developed and new insights in the trade and processing of mineral raw materials are gained based on interdisciplinary archaeological and archaeometrical research. An innovative methodology for and a practical provenance database of the primary origin of natron glass from the Hellenistic-Roman world will be established. The project investigates both production and consumer sites of glass raw materials using both typo-chronological and archaeometrical (isotope geochemical) study of finished glass artefacts at consumer sites as well as mineralogical and chemical characterisation of raw glass and mineral resources at primary production sites. Suitable sand resources in the locations described by ancient authors will be identified through geological prospecting on the basis of literature review and field work. Sand and flux (natron) deposits will be mineralogically and geochemically characterised and compared to the results of the archaeological and geochemical investigations of the glass. Through integrated typo-chronological and archaeometrical analysis, the possible occurrence of primary production centres of raw glass outside the known locations in Syro-Palestine and Egypt, particularly in North-Africa, Italy, Spain and Gaul will be critically studied. In this way, historical, archaeological and archaeometrical data are combined, developing new interdisciplinary techniques for innovative archaeological interpretation of glass trade in the Hellenistic-Roman world.
Summary
In this project, innovative techniques to reconstruct ancient economies are developed and new insights in the trade and processing of mineral raw materials are gained based on interdisciplinary archaeological and archaeometrical research. An innovative methodology for and a practical provenance database of the primary origin of natron glass from the Hellenistic-Roman world will be established. The project investigates both production and consumer sites of glass raw materials using both typo-chronological and archaeometrical (isotope geochemical) study of finished glass artefacts at consumer sites as well as mineralogical and chemical characterisation of raw glass and mineral resources at primary production sites. Suitable sand resources in the locations described by ancient authors will be identified through geological prospecting on the basis of literature review and field work. Sand and flux (natron) deposits will be mineralogically and geochemically characterised and compared to the results of the archaeological and geochemical investigations of the glass. Through integrated typo-chronological and archaeometrical analysis, the possible occurrence of primary production centres of raw glass outside the known locations in Syro-Palestine and Egypt, particularly in North-Africa, Italy, Spain and Gaul will be critically studied. In this way, historical, archaeological and archaeometrical data are combined, developing new interdisciplinary techniques for innovative archaeological interpretation of glass trade in the Hellenistic-Roman world.
Max ERC Funding
954 960 €
Duration
Start date: 2009-11-01, End date: 2014-10-31
Project acronym ARENA
Project Arrays of entangled atoms
Researcher (PI) Antoine Browaeys
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE2, ERC-2009-StG
Summary The goal of this project is to prepare in a deterministic way, and then to characterize, various entangled states of up to 25 individual atoms held in an array of optical tweezers. Such a system provides a new arena to explore quantum entangled states of a large number of particles. Entanglement is the existence of quantum correlations between different parts of a system, and it is recognized as an essential property that distinguishes the quantum and the classical worlds. It is also a resource in various areas of physics, such as quantum information processing, quantum metrology, correlated quantum systems and quantum simulation. In the proposed design, each site is individually addressable, which enables single atom manipulation and detection. This will provide the largest entangled state ever produced and fully characterized at the individual particle level. The experiment will be implemented by combining two crucial novel features, that I was able to demonstrate very recently: first, the manipulation of quantum bits written on long-lived hyperfine ground states of single ultra-cold atoms trapped in microscopic optical tweezers; second, the generation of entanglement by using the strong long-range interactions between Rydberg states. These interactions lead to the so-called dipole blockade , and enable the preparation of various classes of entangled states, such as states carrying only one excitation (W states), and states analogous to Schrödinger s cats (GHZ states). Finally, I will also explore strategies to protect these states against decoherence, developed in the framework of fault-tolerant and topological quantum computing. This project therefore combines an experimental challenge and the exploration of entanglement in a mesoscopic system.
Summary
The goal of this project is to prepare in a deterministic way, and then to characterize, various entangled states of up to 25 individual atoms held in an array of optical tweezers. Such a system provides a new arena to explore quantum entangled states of a large number of particles. Entanglement is the existence of quantum correlations between different parts of a system, and it is recognized as an essential property that distinguishes the quantum and the classical worlds. It is also a resource in various areas of physics, such as quantum information processing, quantum metrology, correlated quantum systems and quantum simulation. In the proposed design, each site is individually addressable, which enables single atom manipulation and detection. This will provide the largest entangled state ever produced and fully characterized at the individual particle level. The experiment will be implemented by combining two crucial novel features, that I was able to demonstrate very recently: first, the manipulation of quantum bits written on long-lived hyperfine ground states of single ultra-cold atoms trapped in microscopic optical tweezers; second, the generation of entanglement by using the strong long-range interactions between Rydberg states. These interactions lead to the so-called dipole blockade , and enable the preparation of various classes of entangled states, such as states carrying only one excitation (W states), and states analogous to Schrödinger s cats (GHZ states). Finally, I will also explore strategies to protect these states against decoherence, developed in the framework of fault-tolerant and topological quantum computing. This project therefore combines an experimental challenge and the exploration of entanglement in a mesoscopic system.
Max ERC Funding
1 449 600 €
Duration
Start date: 2009-12-01, End date: 2014-11-30
Project acronym ASPIRE
Project Aqueous Supramolecular Polymers and Peptide Conjugates in Reversible Systems
Researcher (PI) Oren Alexander Scherman
Host Institution (HI) THE CHANCELLOR MASTERS AND SCHOLARS OF THE UNIVERSITY OF CAMBRIDGE
Country United Kingdom
Call Details Starting Grant (StG), PE5, ERC-2009-StG
Summary Supramolecular polymers are of major interest in the field of self assembly with a promising outlook in areas of viscosity modification, compartmentalized architectures, bio-conjugates and drug-delivery applications. They are dynamic macromolecular materials prepared by simple mixing of relatively small components bearing complementary or self-complementary recognition motifs. A major limitation in the field, however, has been access to synthetic systems capable of undergoing self assembly in an aqueous environment. This research proposal develops well-defined, self-organizing macromolecular structures that will overcome this limitation by focusing on systems that rely on several non-covalent interactions occurring in concert rather than on single interactions alone. The envisioned supramolecular polymers and bio-conjugates are designed as dynamic water-soluble smart materials, whose architectures can be controlled and exhibit reversibility upon exposure to external stimuli such as electrochemical, temperature or pH changes. Molecular recognition events occurring between functional handles on both synthetic and bio-polymers will be investigated in order to control the formation of desired functional architectures through stoichiometrically controlled complexation. Preparation of synthetic core motifs to assemble discrete peptide aggregates such as the dimeric through hexameric oligomers of amyloid-beta(40/42) will lead to structural elucidation and insight into several peptide misfolding pathologies like Alzheimer's or Parkinson's disease.
Summary
Supramolecular polymers are of major interest in the field of self assembly with a promising outlook in areas of viscosity modification, compartmentalized architectures, bio-conjugates and drug-delivery applications. They are dynamic macromolecular materials prepared by simple mixing of relatively small components bearing complementary or self-complementary recognition motifs. A major limitation in the field, however, has been access to synthetic systems capable of undergoing self assembly in an aqueous environment. This research proposal develops well-defined, self-organizing macromolecular structures that will overcome this limitation by focusing on systems that rely on several non-covalent interactions occurring in concert rather than on single interactions alone. The envisioned supramolecular polymers and bio-conjugates are designed as dynamic water-soluble smart materials, whose architectures can be controlled and exhibit reversibility upon exposure to external stimuli such as electrochemical, temperature or pH changes. Molecular recognition events occurring between functional handles on both synthetic and bio-polymers will be investigated in order to control the formation of desired functional architectures through stoichiometrically controlled complexation. Preparation of synthetic core motifs to assemble discrete peptide aggregates such as the dimeric through hexameric oligomers of amyloid-beta(40/42) will lead to structural elucidation and insight into several peptide misfolding pathologies like Alzheimer's or Parkinson's disease.
Max ERC Funding
1 700 000 €
Duration
Start date: 2009-11-01, End date: 2015-10-31
Project acronym ATMOFLEX
Project Turbulent Transport in the Atmosphere: Fluctuations and Extreme Events
Researcher (PI) Jeremie Bec
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE3, ERC-2009-StG
Summary A major part of the physical and chemical processes occurring in the atmosphere involves the turbulent transport of tiny particles. Current studies and models use a formulation in terms of mean fields, where the strong variations in the dynamical and statistical properties of the particles are neglected and where the underlying fluctuations of the fluid flow velocity are oversimplified. Devising an accurate understanding of the influence of air turbulence and of the extreme fluctuations that it generates in the dispersed phase remains a challenging issue. This project aims at coordinating and integrating theoretical, numerical, experimental, and observational efforts to develop a new statistical understanding of the role of fluctuations in atmospheric transport processes. The proposed work will cover individual as well as collective behaviors and will provide a systematic and unified description of targeted specific processes involving suspended drops or particles: the dispersion of pollutants from a source, the growth by condensation and coagulation of droplets and ice crystals in clouds, the scavenging, settling and re-suspension of aerosols, and the radiative and climatic effects of particles. The proposed approach is based on the use of tools borrowed from statistical physics and field theory, and from the theory of large deviations and of random dynamical systems in order to design new observables that will be simultaneously tractable analytically in simplified models and of relevance for the quantitative handling of such physical mechanisms. One of the outcomes will be to provide a new framework for improving and refining the methods used in meteorology and atmospheric sciences and to answer the long-standing question of the effects of suspended particles onto climate.
Summary
A major part of the physical and chemical processes occurring in the atmosphere involves the turbulent transport of tiny particles. Current studies and models use a formulation in terms of mean fields, where the strong variations in the dynamical and statistical properties of the particles are neglected and where the underlying fluctuations of the fluid flow velocity are oversimplified. Devising an accurate understanding of the influence of air turbulence and of the extreme fluctuations that it generates in the dispersed phase remains a challenging issue. This project aims at coordinating and integrating theoretical, numerical, experimental, and observational efforts to develop a new statistical understanding of the role of fluctuations in atmospheric transport processes. The proposed work will cover individual as well as collective behaviors and will provide a systematic and unified description of targeted specific processes involving suspended drops or particles: the dispersion of pollutants from a source, the growth by condensation and coagulation of droplets and ice crystals in clouds, the scavenging, settling and re-suspension of aerosols, and the radiative and climatic effects of particles. The proposed approach is based on the use of tools borrowed from statistical physics and field theory, and from the theory of large deviations and of random dynamical systems in order to design new observables that will be simultaneously tractable analytically in simplified models and of relevance for the quantitative handling of such physical mechanisms. One of the outcomes will be to provide a new framework for improving and refining the methods used in meteorology and atmospheric sciences and to answer the long-standing question of the effects of suspended particles onto climate.
Max ERC Funding
1 200 000 €
Duration
Start date: 2009-11-01, End date: 2014-10-31
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
Country Germany
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
