Project acronym 1st-principles-discs
Project A First Principles Approach to Accretion Discs
Researcher (PI) Martin Elias Pessah
Host Institution (HI) KOBENHAVNS UNIVERSITET
Call Details Starting Grant (StG), PE9, ERC-2012-StG_20111012
Summary Most celestial bodies, from planets, to stars, to black holes; gain mass during their lives by means of an accretion disc. Understanding the physical processes that determine the rate at which matter accretes and energy is radiated in these discs is vital for unraveling the formation, evolution, and fate of almost every type of object in the Universe. Despite the fact that magnetic fields have been known to be crucial in accretion discs since the early 90’s, the majority of astrophysical questions that depend on the details of how disc accretion proceeds are still being addressed using the “standard” accretion disc model (developed in the early 70’s), where magnetic fields do not play an explicit role. This has prevented us from fully exploring the astrophysical consequences and observational signatures of realistic accretion disc models, leading to a profound disconnect between observations (usually interpreted with the standard paradigm) and modern accretion disc theory and numerical simulations (where magnetic turbulence is crucial). The goal of this proposal is to use several complementary approaches in order to finally move beyond the standard paradigm. This program has two main objectives: 1) Develop the theoretical framework to incorporate magnetic fields, and the ensuing turbulence, into self-consistent accretion disc models, and investigate their observational implications. 2) Investigate transport and radiative processes in collision-less disc regions, where non-thermal radiation originates, by employing a kinetic particle description of the plasma. In order to achieve these goals, we will use, and build upon, state-of-the-art magnetohydrodynamic and particle-in-cell codes in conjunction with theoretical modeling. This framework will make it possible to address fundamental questions on stellar and planet formation, binary systems with a compact object, and supermassive black hole feedback in a way that has no counterpart within the standard paradigm.
Summary
Most celestial bodies, from planets, to stars, to black holes; gain mass during their lives by means of an accretion disc. Understanding the physical processes that determine the rate at which matter accretes and energy is radiated in these discs is vital for unraveling the formation, evolution, and fate of almost every type of object in the Universe. Despite the fact that magnetic fields have been known to be crucial in accretion discs since the early 90’s, the majority of astrophysical questions that depend on the details of how disc accretion proceeds are still being addressed using the “standard” accretion disc model (developed in the early 70’s), where magnetic fields do not play an explicit role. This has prevented us from fully exploring the astrophysical consequences and observational signatures of realistic accretion disc models, leading to a profound disconnect between observations (usually interpreted with the standard paradigm) and modern accretion disc theory and numerical simulations (where magnetic turbulence is crucial). The goal of this proposal is to use several complementary approaches in order to finally move beyond the standard paradigm. This program has two main objectives: 1) Develop the theoretical framework to incorporate magnetic fields, and the ensuing turbulence, into self-consistent accretion disc models, and investigate their observational implications. 2) Investigate transport and radiative processes in collision-less disc regions, where non-thermal radiation originates, by employing a kinetic particle description of the plasma. In order to achieve these goals, we will use, and build upon, state-of-the-art magnetohydrodynamic and particle-in-cell codes in conjunction with theoretical modeling. This framework will make it possible to address fundamental questions on stellar and planet formation, binary systems with a compact object, and supermassive black hole feedback in a way that has no counterpart within the standard paradigm.
Max ERC Funding
1 793 697 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym DropletControl
Project Controlling the orientation of molecules inside liquid helium nanodroplets
Researcher (PI) Henrik Stapelfeldt
Host Institution (HI) AARHUS UNIVERSITET
Call Details Advanced Grant (AdG), PE2, ERC-2012-ADG_20120216
Summary In this project I will develop and exploit experimental methods, based on short and intense laser pulses, to control the spatial orientation of molecules dissolved in liquid helium nanodroplets. This idea is, so far, completely unexplored but it has the potential to open a multitude of new opportunities in physics and chemistry. The main objectives are:
1) Complete control and real time monitoring of molecular rotation inside liquid helium droplets, exploring superfluidity of the droplets, the possible formation of quantum vortices, and rotational dephasing due to interaction of the dissolved molecules with the He solvent.
2) Ultrafast imaging of molecules undergoing chemical reaction dynamics inside liquid helium droplets, exploring rapid energy dissipation from reacting molecules to the helium solvent, transition between mirror forms of chiral molecules, strong laser field processes in He-solvated molecules, and structure determination of non crystalizable proteins by electron or x-ray diffraction.
I will achieve the objectives by combining liquid helium droplet technology, ultrafast laser pulse methods and advanced electron and ion imaging detection. The experiments will both rely on existing apparatus in my laboratories and on new vacuum and laser equipment to be set up during the project.
The ability to control how molecules are turned in space is of fundamental importance because interactions of molecules with other molecules, atoms or radiation depend on their spatial orientation. For isolated molecules in the gas phase laser based methods, developed over the past 12 years, now enable very refined and precise control over the spatial orientation of molecules. By contrast, orientational control of molecules in solution has not been demonstrated despite the potential of being able to do so is enormous, notably because most chemistry occurs in a solvent rather than in a gas of isolated molecules.
Summary
In this project I will develop and exploit experimental methods, based on short and intense laser pulses, to control the spatial orientation of molecules dissolved in liquid helium nanodroplets. This idea is, so far, completely unexplored but it has the potential to open a multitude of new opportunities in physics and chemistry. The main objectives are:
1) Complete control and real time monitoring of molecular rotation inside liquid helium droplets, exploring superfluidity of the droplets, the possible formation of quantum vortices, and rotational dephasing due to interaction of the dissolved molecules with the He solvent.
2) Ultrafast imaging of molecules undergoing chemical reaction dynamics inside liquid helium droplets, exploring rapid energy dissipation from reacting molecules to the helium solvent, transition between mirror forms of chiral molecules, strong laser field processes in He-solvated molecules, and structure determination of non crystalizable proteins by electron or x-ray diffraction.
I will achieve the objectives by combining liquid helium droplet technology, ultrafast laser pulse methods and advanced electron and ion imaging detection. The experiments will both rely on existing apparatus in my laboratories and on new vacuum and laser equipment to be set up during the project.
The ability to control how molecules are turned in space is of fundamental importance because interactions of molecules with other molecules, atoms or radiation depend on their spatial orientation. For isolated molecules in the gas phase laser based methods, developed over the past 12 years, now enable very refined and precise control over the spatial orientation of molecules. By contrast, orientational control of molecules in solution has not been demonstrated despite the potential of being able to do so is enormous, notably because most chemistry occurs in a solvent rather than in a gas of isolated molecules.
Max ERC Funding
2 409 773 €
Duration
Start date: 2013-05-01, End date: 2018-04-30
Project acronym GRACOL
Project Graph Theory: Colourings, flows, and decompositions
Researcher (PI) Carsten Thomassen
Host Institution (HI) DANMARKS TEKNISKE UNIVERSITET
Call Details Advanced Grant (AdG), PE1, ERC-2012-ADG_20120216
Summary Graph theory is a relatively new branch of mathematics. Early sources of inspiration are Kirchhoff’s theory of electrical networks and the 4-color problem, both from the 19th century. In the 20th century graph theory was one of the most rapidly growing branches of mathematics with applications to theoretical computer science (design and analysis of algorithms), operations research (combinatorial optimization) and models in engineering and economics. The internet may be thought as a graph. There are also strong ties to geometry, topology, probability theory and logic.
The main subjects in the project are graphs in the plane and on higher surfaces, graph decomposition, the Tutte polynomial and the graph flow conjectures, and also combinatorial problems arising from differential geometry. The project is centered around applying new approaches to some classical problems in graph theory, in particular problems in chromatic graph theory and flow theory. In some sense these problems have an algebraic unification in the Tutte polynomial of two variables. The Tutte polynomial has as special valuations (fixing one of the variables) the chromatic polynomial (introduced in 1912 by Birkhoff) and the flow polynomial. More recently, the Tutte polynomial has also become of interest in statistical mechanics.
Among the specific problems to be investigated is Tutte’s 3-flow conjecture from the early 1970es, the problem if the flow polynomial can have arbitrarily large roots (motivated by Tutte’s 5-flow conjecture), the Merino-Welsh conjecture on the numbers of spanning trees, acyclic orientations and totally cyclic orientations, and Wegner’s conjecture from 1977 about squares of planar cubic graphs. We expect to get significant new insight (but not complete solutions) to the two notoriously hard flow conjectures of Tutte (both of which are also described in Wikipedia). We expect to almost solve the Merino-Welsh conjecture. We expect to completely solve the Wegner conjecture.
Summary
Graph theory is a relatively new branch of mathematics. Early sources of inspiration are Kirchhoff’s theory of electrical networks and the 4-color problem, both from the 19th century. In the 20th century graph theory was one of the most rapidly growing branches of mathematics with applications to theoretical computer science (design and analysis of algorithms), operations research (combinatorial optimization) and models in engineering and economics. The internet may be thought as a graph. There are also strong ties to geometry, topology, probability theory and logic.
The main subjects in the project are graphs in the plane and on higher surfaces, graph decomposition, the Tutte polynomial and the graph flow conjectures, and also combinatorial problems arising from differential geometry. The project is centered around applying new approaches to some classical problems in graph theory, in particular problems in chromatic graph theory and flow theory. In some sense these problems have an algebraic unification in the Tutte polynomial of two variables. The Tutte polynomial has as special valuations (fixing one of the variables) the chromatic polynomial (introduced in 1912 by Birkhoff) and the flow polynomial. More recently, the Tutte polynomial has also become of interest in statistical mechanics.
Among the specific problems to be investigated is Tutte’s 3-flow conjecture from the early 1970es, the problem if the flow polynomial can have arbitrarily large roots (motivated by Tutte’s 5-flow conjecture), the Merino-Welsh conjecture on the numbers of spanning trees, acyclic orientations and totally cyclic orientations, and Wegner’s conjecture from 1977 about squares of planar cubic graphs. We expect to get significant new insight (but not complete solutions) to the two notoriously hard flow conjectures of Tutte (both of which are also described in Wikipedia). We expect to almost solve the Merino-Welsh conjecture. We expect to completely solve the Wegner conjecture.
Max ERC Funding
1 518 471 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym HARMONY
Project "Harmonic identification, mitigation and control in power electronics based power systems"
Researcher (PI) Frede Blåbjerg
Host Institution (HI) AALBORG UNIVERSITET
Call Details Advanced Grant (AdG), PE7, ERC-2012-ADG_20120216
Summary "Global electrical energy consumption is still increasing which demands that power capacity and power transmission capabilities must be doubled within 20 years. Today 40 % of the global energy consumption is processed by electricity in 2040 this may be up to 70 %. Electrical power production is changing from conventional, fossil based sources to renewable power resources. Highly efficient and sustainable power electronics in power generation, power transmission/distribution and end-user applications are introduced to ensure more efficient use of electricity. Traditional centralized electricity production with unidirectional power flows in transmission and distribution system will be replaced by the operation and control of intelligent distribution systems which are much more based on power electronics systems and having bidirectional power flow. Such large scale expansion of power electronics usage will change the characteristic of the power system by introducing more harmonics from generation, from the efficient load systems all resulting in a larger risk of instability and more losses in the future power system. The projects goal is to obtain “Harmony” between the renewable energy sources, the future power system and the loads in order to keep stability at all levels seen from a harmonic point of view. The project establishes the necessary theories, models and methods to identify harmonic problems in a power electronic based power system, a theoretical and hardware platform to enable control of harmonics and mitigate them, and develops on-line methods to monitor the harmonic state of the power system. The outcomes are new tools for identifying stability problems in power electronics based power systems and new control methods for reducing the harmonic presence and reduce the overall instability risks. Further, new design methods for active and passive filters in renewable energy systems, in the power system and in the power electronics based loads will be developed"
Summary
"Global electrical energy consumption is still increasing which demands that power capacity and power transmission capabilities must be doubled within 20 years. Today 40 % of the global energy consumption is processed by electricity in 2040 this may be up to 70 %. Electrical power production is changing from conventional, fossil based sources to renewable power resources. Highly efficient and sustainable power electronics in power generation, power transmission/distribution and end-user applications are introduced to ensure more efficient use of electricity. Traditional centralized electricity production with unidirectional power flows in transmission and distribution system will be replaced by the operation and control of intelligent distribution systems which are much more based on power electronics systems and having bidirectional power flow. Such large scale expansion of power electronics usage will change the characteristic of the power system by introducing more harmonics from generation, from the efficient load systems all resulting in a larger risk of instability and more losses in the future power system. The projects goal is to obtain “Harmony” between the renewable energy sources, the future power system and the loads in order to keep stability at all levels seen from a harmonic point of view. The project establishes the necessary theories, models and methods to identify harmonic problems in a power electronic based power system, a theoretical and hardware platform to enable control of harmonics and mitigate them, and develops on-line methods to monitor the harmonic state of the power system. The outcomes are new tools for identifying stability problems in power electronics based power systems and new control methods for reducing the harmonic presence and reduce the overall instability risks. Further, new design methods for active and passive filters in renewable energy systems, in the power system and in the power electronics based loads will be developed"
Max ERC Funding
2 500 000 €
Duration
Start date: 2013-03-01, End date: 2018-02-28
Project acronym HBAR12
Project Spectroscopy of Trapped Antihydrogen
Researcher (PI) Jeffrey Scott Hangst
Host Institution (HI) AARHUS UNIVERSITET
Call Details Advanced Grant (AdG), PE2, ERC-2012-ADG_20120216
Summary Antihydrogen is the only stable, neutral antimatter system available for laboratory study. Recently, the ALPHA Collaboration at CERN has succeeded in synthesizing and trapping antihydrogen atoms, storing them for up to 1000 s, and performing the first resonant spectroscopy, using microwaves, on trapped antihydrogen. This last, historic result paves the way for precision microwave and laser spectroscopic measurements using small numbers of trapped antihydrogen atoms. Because of the breakthroughs made in our collaboration, it is now possible, for the first time, to design antimatter spectroscopic experiments that have achievable milestones of precision. These measurements require a next-generation apparatus, known as ALPHA-2, which is the subject of this proposal. The items sought are hardware components and radiation sources to help us to test CPT (charge conjugation, parity, time reversal) symmetry invariance by comparing the spectrum of antihydrogen to that of hydrogen. More generally, we will address the very fundamental question: do matter and antimatter obey the same laws of physics? The Standard Model says that they must, but mystery continues to cloud our understanding of antimatter - as evidenced by the unexplained baryon asymmetry in the universe. ALPHA's experiments offer a unique, high precision, model-independent view into the internal workings of antimatter.
Summary
Antihydrogen is the only stable, neutral antimatter system available for laboratory study. Recently, the ALPHA Collaboration at CERN has succeeded in synthesizing and trapping antihydrogen atoms, storing them for up to 1000 s, and performing the first resonant spectroscopy, using microwaves, on trapped antihydrogen. This last, historic result paves the way for precision microwave and laser spectroscopic measurements using small numbers of trapped antihydrogen atoms. Because of the breakthroughs made in our collaboration, it is now possible, for the first time, to design antimatter spectroscopic experiments that have achievable milestones of precision. These measurements require a next-generation apparatus, known as ALPHA-2, which is the subject of this proposal. The items sought are hardware components and radiation sources to help us to test CPT (charge conjugation, parity, time reversal) symmetry invariance by comparing the spectrum of antihydrogen to that of hydrogen. More generally, we will address the very fundamental question: do matter and antimatter obey the same laws of physics? The Standard Model says that they must, but mystery continues to cloud our understanding of antimatter - as evidenced by the unexplained baryon asymmetry in the universe. ALPHA's experiments offer a unique, high precision, model-independent view into the internal workings of antimatter.
Max ERC Funding
2 136 888 €
Duration
Start date: 2013-05-01, End date: 2018-12-31
Project acronym HERMES
Project HERMES – High Exponential Rise in Miniaturized cantilever-like Sensing
Researcher (PI) Anja Boisen
Host Institution (HI) DANMARKS TEKNISKE UNIVERSITET
Call Details Advanced Grant (AdG), PE8, ERC-2012-ADG_20120216
Summary Miniaturized cantilever–like sensors have evolved rapidly. However, when it comes to major breakthroughs in both fundamental studies as well as commercial applications these sensors face severe challenges: i) reliability – often only one or two measurements are performed for the same conditions due to very slow data generation and the results are rarely confirmed by orthogonal sensing technologies, ii) sensitivity – in many applications the need is now for ultra-low sensitivities, iii) reproducibility – very few results have been reported on reproducibility of these sensors iv)throughput –extremely slow and tedious read-out technologies. In order to take a great leap forward in cantilever-like sensing I suggest a new generation of simplified and optimized cantilever-like sensing structures implemented in a DVD based platform which will specifically address these issues.
My overall hypothesis is that the true potential of these exciting sensors can only be released when using a simple and reliable read-out system that allows us to focus on the mechanical performance of the sensors. Thus we will keep the sensors as simple as possible. The DVD readout makes it possible to generate large amount of data and to focus on mechanics and the interplay between mechanics, optics and electrochemistry. It will be a technological challenge to realize a robust and reliable DVD platform, that facilitates optical read-out as well as actuation. The DVD platform will enable a fast and iterative development of hybrid cantilever-like systems which draw upon our more than 10 years experience in the field. These sensors will be realised using Si and polymer based cleanroom fabrication. Focus is on design, fabrication, characterization and applications of cantilever-like sensors and on DVD inspired system integration. By the end of HERMES we will have a unique platform which will be the onset of many new types of specific high –throughput applications and sensor development projects.
Summary
Miniaturized cantilever–like sensors have evolved rapidly. However, when it comes to major breakthroughs in both fundamental studies as well as commercial applications these sensors face severe challenges: i) reliability – often only one or two measurements are performed for the same conditions due to very slow data generation and the results are rarely confirmed by orthogonal sensing technologies, ii) sensitivity – in many applications the need is now for ultra-low sensitivities, iii) reproducibility – very few results have been reported on reproducibility of these sensors iv)throughput –extremely slow and tedious read-out technologies. In order to take a great leap forward in cantilever-like sensing I suggest a new generation of simplified and optimized cantilever-like sensing structures implemented in a DVD based platform which will specifically address these issues.
My overall hypothesis is that the true potential of these exciting sensors can only be released when using a simple and reliable read-out system that allows us to focus on the mechanical performance of the sensors. Thus we will keep the sensors as simple as possible. The DVD readout makes it possible to generate large amount of data and to focus on mechanics and the interplay between mechanics, optics and electrochemistry. It will be a technological challenge to realize a robust and reliable DVD platform, that facilitates optical read-out as well as actuation. The DVD platform will enable a fast and iterative development of hybrid cantilever-like systems which draw upon our more than 10 years experience in the field. These sensors will be realised using Si and polymer based cleanroom fabrication. Focus is on design, fabrication, characterization and applications of cantilever-like sensors and on DVD inspired system integration. By the end of HERMES we will have a unique platform which will be the onset of many new types of specific high –throughput applications and sensor development projects.
Max ERC Funding
2 499 466 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym LOBENA
Project Long Beamtime Experiments for Nuclear Astrophysics
Researcher (PI) Hans Otto Uldall Fynbo
Host Institution (HI) AARHUS UNIVERSITET
Call Details Starting Grant (StG), PE2, ERC-2012-StG_20111012
Summary The goal of LOBENA is to measure key properties needed for understanding nuclear processes in the Cosmos. Nuclear Astrophysics plays a key role in our quest to understand the origin and distribution of the chemical elements in our galaxy. Nuclear processes are crucial for understanding the energy production in the universe and are essential for describing the creation of chemical elements from the ashes of the Big Bang. Uncertainties in the nuclear physics can therefore influence our understanding of many astrophysical processes, both those involving stable stellar burning phases and explosive phenomena such as X-ray bursts, gamma-ray bursts and supernovae.
In LOBENA (LOng Beamtime Experiments for Nuclear Astrophysics) I will initiate a series of studies in Nuclear Astrophysics, which have in common the need for long beam times and the use of complete kinematics detection of several particles emitted in reactions. The core of the project will focus on the systems 8Be, 12C and 16O where today key open questions of great importance remain to answered. These questions can be addressed by reactions induced by low energy (<5MeV) beams of protons and 3He on light targets such as 6,7Li, 9Be, 10,11B and 19F using a newly developed complete kinematics detection procedure. The department of Physics and Astronomy in Aarhus provides a unique scene for doing these measurements since it provides accelerators where long beam time can be guarantied. LOBENA will also include complimentary experiments at international user facilities such as ISOLDE (CERN), KVI (Groningen), JYFL and (Jyväskylä).
With this ERC starting grant proposal I wish to start up my own group around Nuclear Astrophysics experiments in house and at international user facilities. With two Post Doc.s and a Ph.D. I will be much better able to fully exploit the scientific potential of the proposed research, which will also help to consolidate my own research career and give me more independence.
Summary
The goal of LOBENA is to measure key properties needed for understanding nuclear processes in the Cosmos. Nuclear Astrophysics plays a key role in our quest to understand the origin and distribution of the chemical elements in our galaxy. Nuclear processes are crucial for understanding the energy production in the universe and are essential for describing the creation of chemical elements from the ashes of the Big Bang. Uncertainties in the nuclear physics can therefore influence our understanding of many astrophysical processes, both those involving stable stellar burning phases and explosive phenomena such as X-ray bursts, gamma-ray bursts and supernovae.
In LOBENA (LOng Beamtime Experiments for Nuclear Astrophysics) I will initiate a series of studies in Nuclear Astrophysics, which have in common the need for long beam times and the use of complete kinematics detection of several particles emitted in reactions. The core of the project will focus on the systems 8Be, 12C and 16O where today key open questions of great importance remain to answered. These questions can be addressed by reactions induced by low energy (<5MeV) beams of protons and 3He on light targets such as 6,7Li, 9Be, 10,11B and 19F using a newly developed complete kinematics detection procedure. The department of Physics and Astronomy in Aarhus provides a unique scene for doing these measurements since it provides accelerators where long beam time can be guarantied. LOBENA will also include complimentary experiments at international user facilities such as ISOLDE (CERN), KVI (Groningen), JYFL and (Jyväskylä).
With this ERC starting grant proposal I wish to start up my own group around Nuclear Astrophysics experiments in house and at international user facilities. With two Post Doc.s and a Ph.D. I will be much better able to fully exploit the scientific potential of the proposed research, which will also help to consolidate my own research career and give me more independence.
Max ERC Funding
1 476 075 €
Duration
Start date: 2012-11-01, End date: 2018-10-31
Project acronym MASTRUMAT
Project The Mathematics of the Structure of Matter
Researcher (PI) Jan Philip Solovej
Host Institution (HI) KOBENHAVNS UNIVERSITET
Call Details Advanced Grant (AdG), PE1, ERC-2012-ADG_20120216
Summary "The objective of the proposed research in mathematical physics is to study the quantum theory of matter from a mathematical perspective. We will consider systems ranging from the tiny scale of atoms over macroscopic everyday matter to the gigantic scale of stars. Despite the range in scale, these systems may all be described by many-body quantum physics. Our aim is to rigorously understand their stability and structure, in particular, exotic phenomena such as Bose-Einstein condensation, superconductivity, superfluidity, and special low-dimensional behavior. The ultimate goal is to understand the full many-body theory but we will also investigate simpler approximate models such as Bogolubov’s model for superfluidity, Bardeen-Cooper-Schrieffer (BCS) and Ginzburg-Landau (GL) models of superconductivity, and the Hartree-Fock model of atoms and molecules. The role of such models is two-fold. On one hand they are of independent interest. On the other hand and more importantly they may give information about the many-body theory. This is true to the extent we can estimate the degree to which they approximate in appropriate limits.
From a mathematical point of view our approach is variational. All the theories we consider are formulated in terms of energy functionals. The full many-body theories are linear but due to the essentially uncontrolled number of variables they are extremely complicated. The approximate models are non-linear. Surprisingly they are nevertheless significantly simpler due to the reduction in degrees of freedom. Often the limits correspond to semiclassical limits for spectral problems.
Examples of specific goals that we will pursue are
*Establish the thermodynamic properties of matter coupled to electromagnetic fields
*Derive GL theory as a limit of BCS theory
*Estimate ionization energies of large atoms and molecules
*Derive spectral estimates of Lieb-Thirring type for 2D anyons
*Derive semiclassical expansions for problems with low regularity"
Summary
"The objective of the proposed research in mathematical physics is to study the quantum theory of matter from a mathematical perspective. We will consider systems ranging from the tiny scale of atoms over macroscopic everyday matter to the gigantic scale of stars. Despite the range in scale, these systems may all be described by many-body quantum physics. Our aim is to rigorously understand their stability and structure, in particular, exotic phenomena such as Bose-Einstein condensation, superconductivity, superfluidity, and special low-dimensional behavior. The ultimate goal is to understand the full many-body theory but we will also investigate simpler approximate models such as Bogolubov’s model for superfluidity, Bardeen-Cooper-Schrieffer (BCS) and Ginzburg-Landau (GL) models of superconductivity, and the Hartree-Fock model of atoms and molecules. The role of such models is two-fold. On one hand they are of independent interest. On the other hand and more importantly they may give information about the many-body theory. This is true to the extent we can estimate the degree to which they approximate in appropriate limits.
From a mathematical point of view our approach is variational. All the theories we consider are formulated in terms of energy functionals. The full many-body theories are linear but due to the essentially uncontrolled number of variables they are extremely complicated. The approximate models are non-linear. Surprisingly they are nevertheless significantly simpler due to the reduction in degrees of freedom. Often the limits correspond to semiclassical limits for spectral problems.
Examples of specific goals that we will pursue are
*Establish the thermodynamic properties of matter coupled to electromagnetic fields
*Derive GL theory as a limit of BCS theory
*Estimate ionization energies of large atoms and molecules
*Derive spectral estimates of Lieb-Thirring type for 2D anyons
*Derive semiclassical expansions for problems with low regularity"
Max ERC Funding
1 465 016 €
Duration
Start date: 2013-04-01, End date: 2018-03-31
Project acronym QIOS
Project Quantum Interfaces and Open Systems
Researcher (PI) Anders Sørensen
Host Institution (HI) KOBENHAVNS UNIVERSITET
Call Details Starting Grant (StG), PE2, ERC-2012-StG_20111012
Summary "Researchers have strived to obtain control of a variety of different quantum systems, each characterized by their own distinct advantages: quantum optical systems offer excellent isolation from the environment while solid state systems allow for integrated micro-fabricated devices. At the same time nuclear spins in molecules can remain decoupled from the environment even under rather harsh conditions, and this is the basis of NMR experiments. Given these distinct advantages it is very fruitful to investigate hybrid devices merging the advantages of each of the systems. To do this it is essential to develop quantum interfaces to connect the different systems. By their very nature such quantum interfaces exchange information with their environment and are therefore open quantum systems.
In this project I wish to establish a strong theoretical quantum optics group which can guide and inspire the experiments towards breaking new grounds for open quantum systems and making quantum interfaces between distinct physical systems. The objective is to develop concrete proposals for how to experimentally control and exploit the interaction of quantum systems with their surroundings and for how this can be used for quantum interfaces.
The work in this project is particularly relevant for applications in quantum information processing, where the current challenge is to take the field from proof-of-principle demonstrations to truly scalable devices. Such challenge demands new interdisciplinary theoretical ideas for hybrid devices. This proposal addresses several key challenges for quantum information processing: scalable multimode quantum repeaters based on hybrid approaches, entanglement enabled quantum metrology, photonic engineering based on surface plasmons, dissipative preparation of entangled states, and phonon engineering for quantum dots. In addition applications towards nuclear spin cooling to improve NMR experiments as well as ultra cold atoms will be explored."
Summary
"Researchers have strived to obtain control of a variety of different quantum systems, each characterized by their own distinct advantages: quantum optical systems offer excellent isolation from the environment while solid state systems allow for integrated micro-fabricated devices. At the same time nuclear spins in molecules can remain decoupled from the environment even under rather harsh conditions, and this is the basis of NMR experiments. Given these distinct advantages it is very fruitful to investigate hybrid devices merging the advantages of each of the systems. To do this it is essential to develop quantum interfaces to connect the different systems. By their very nature such quantum interfaces exchange information with their environment and are therefore open quantum systems.
In this project I wish to establish a strong theoretical quantum optics group which can guide and inspire the experiments towards breaking new grounds for open quantum systems and making quantum interfaces between distinct physical systems. The objective is to develop concrete proposals for how to experimentally control and exploit the interaction of quantum systems with their surroundings and for how this can be used for quantum interfaces.
The work in this project is particularly relevant for applications in quantum information processing, where the current challenge is to take the field from proof-of-principle demonstrations to truly scalable devices. Such challenge demands new interdisciplinary theoretical ideas for hybrid devices. This proposal addresses several key challenges for quantum information processing: scalable multimode quantum repeaters based on hybrid approaches, entanglement enabled quantum metrology, photonic engineering based on surface plasmons, dissipative preparation of entangled states, and phonon engineering for quantum dots. In addition applications towards nuclear spin cooling to improve NMR experiments as well as ultra cold atoms will be explored."
Max ERC Funding
1 431 542 €
Duration
Start date: 2012-10-01, End date: 2017-09-30
