Abstracts of presentations/discussions (a pdf file will be made available here in due course)
1. Decoherence in low-energy nuclear collisions?
Alexis Diaz-Torres
Department of Physics, University of Surrey, UK
2. Decay analysis with reservoir structures
Barry M. Garraway
Department of Physics and Astronomy, University of Sussex, UK
Static reservoir structures coupled to simple quantum systems can be analysed by the method
of "pseudomodes", where the reservoir structure is replaced by an effective mode. The approach
can be useful for strongly coupled, i.e. non-Markovian problems. An introduction to this theory will
be given with some simple examples. The connections with "quantum trajectories" will also be
explored.
3. Hund's paradox and the collisional stabilization of chiral molecules
Klaus Hornberger
Max Planck Institute for the Physics of Complex Systems, Dresden
We identify the dominant collisional decoherence mechanism which serves to stabilize and super-
select the configuration states of chiral molecules. A high-energy description of this effect is
compared to the results of the exact molecular scattering problem, obtained by solving the
coupled-channel equations. It allows to predict the experimental conditions for observing the
collisional suppression of the tunneling dynamics between the left-handed and the right-handed
configuration of D_2 S_2 molecules.
4. Coherence and decoherence of hot, complex molecules
Stefan Gerlich
U-Vienna, Austria
Talbot-Lau interferometry has recently been established as an ideal method to perform quantum
matter wave experiments with large, highly polarizable molecules in the so far inaccessible mass
range of beyond 1000 atomic mass units. Benefits, challenges and potential limits of matter wave
experiments with very massive objects will be addressed.
Especially for thermally excited, complex molecules with a rich structure and dynamics, the interaction
between their internal motion and their centre-of-mass motion has often been considered as a serious
obstacle for de Broglie interferometry. We present ways how information about the internal molecular
properties can be extracted in matter wave experiments without destroying the quantum interference.
5. Control by decoherence: Weak field control of excited state objective
Ronnie Kosloff
Institute of Chemistry, Hebrew University, Jerusalem, Israel
6. Time-dependent approaches to quantum dynamics of many-body systems
Takashi Nakatsukasa
RIKEN, Japan
Solving the time-dependent Schrodinger equation and time-dependent Kohn-Sham equation in real
time in real space, I will discuss the quantum dynamics of many-fermion systems: Nuclear
reaction/fusion, electronic excitation in solids, Coulomb explosion of molecules, etc.
Basic issues addressed in the talk are (1) Advantages and disadvantages of real-time approaches,
(2) Quantum wave-packet dynamics and observables, (3) Dissipative dynamics in time-dependent
DFT and problems.
7. Applying time-local quantum master equations to dissipative dynamics and transport
Ulrich Kleinekathoefer
Jacobs University, Bremen
8. Collective response of atom clusters and nuclei: Role of chaos
Mahir Hussein
USP, Sao Paulo, Brazil
9. Sub-barrier fusion reactions with dissipative couplings
Kouichi Hagino
Tohoku University, Sendai, Japan
10. Aspects of the transition from quasi-elastic to deep inelastic processes
Lorenzo Corradi
INFN Legnaro, Italy
11. Open system density matrix theory for surface science problems
Peter Saalfrank
U-Potsdam, Germany
12. Decoherence of electron waves caused by irreversible electromagnetic interaction with the charges
in a resistive plate
Franz Hasselbach
Univ. Tuebingen, Germany
13. Quantum decoherence of qubits
Walter Strunz
Institut für Theoretische Physik, TU Dresden, Germany
Decoherence in open quantum systems may be due to growing entanglement with an environment. In practice,
however, more often than one might think, decoherence may equally well be described by random unitary
dynamics without invoking a quantum environment at all. I will present examples of qubit decoherence to
clarify the appearance of "true quantum decoherence", i.e. decoherence that is based on system-environment
entanglement rather than unitary noise. For a two qubit example, one can give a very intuitive geometrical
measure for the positive distance of our two-qubit decoherence channel to the convex set of random unitary
channels and find remarkable agreement with the so-called Birkhoff defect based on the norm of complete
boundedness.
14. Open quantum systems with memory
Jyrki Piilo
University of Turku, Finland
We describe how temporary negative decay rates can be associated to memory in the dynamics of open quantum
systems and present non- Markovian quantum jump method to treat such systems. We show how this leads to a
formulation of a novel stochastic process and conclude by discussing about a general measure for the memory of
open systems which is based on characterizing the information flow between the system and its environment.
15. Coherence and decoherence in ultrafast molecular processes: non-Markovian approaches based
upon a hierarchical effective-mode decomposition
Irene Burghardt
ENS, Paris, France
16. Coherent excitation energy transfer in photosynthetic light harvesting systems
David Coker
UCD, Dublin, Ireland
17. Non-Markovian quantum dynamics: a stochastic Schrödinger equation approach
Angelo Bassi
U-Trieste, Italy
18. Quantum coherence and decoherence in low energy nuclear collisions: from superposition to
irreversible outcomes
David Hinde
ANU, Canberra, Australia
19. Shell Model for Open Quantum Systems
Marek Ploszajczak
GANIL, Caen, France
We shall review foundations and applications of the complex-energy continuum shell model that provides a
consistent many-body description of bound states, resonances, and scattering states. The model can be
considered a quasi-stationary open quantum system extension of the standard configuration interaction
approach for well-bound (closed) systems.
20. Coherence and Dissipation in Nuclear Fusion
Mahananda Dasgupta
ANU, Canberra, Australia
Effectively isolated from an external environment, colliding nuclei display dramatic effects of quantum coherence,
resulting in orders of magnitude changes in reaction outcomes. This is clearly seen in fusion cross-sections,
reflecting the changed quantum tunnelling probability.
The coherent coupled-channels model has been successful in describing qualitatively many aspects of nuclear
fusion, including experimental measurements of the fusion barrier distributions. Under certain approximations,
these can be thought of as revealing directly the eigenchannels experienced by the system before irreversible
energy dissipation occurs. The distributions are extracted from the second derivative of the fusion cross-section,
thus such studies require high precision measurements, which required the development of highly efficient and
sensitive detection systems. Recent precise fusion data spanning a wide energy range have brought into
question the assumption that energy dissipation need not be treated explicitly in describing nuclear fusion,
and this question will be discussed in detail.
21. Time-dependent Green's Functions Approach to Nuclear Reactions
Arnau Rios Huguet
Department of Physics, University of Surrey, UK
Nonequilibrium Green's functions represent underutilized means of studying the time evolution of nuclei. For
reactions, this framework can consistently include correlations beyond the mean-field as well as memory
effects associated to complex many-body excitations. These would be relevant for the case of central low-energy
reaction, such as fusion, where quantum many-body as well as dissipative effects fully come into play. In view
of the rising computer power, we want to apply the Green's functions formalism to simulate the dynamics of nuclei.
As a first step, we will describe an attempt to simulate the mean-field dynamics of symmetric reactions for one-
dimensional nuclear slabs. We will pay particular attention to the role of the off-diagonal elements of the Green's
functions and their relation to decoherence. Their relevance for the global time evolution as well as for time
reversibility will be assessed. Finally, the extension of the dynamics to a correlated case, in which the self-
energy is treated within the Born approximation, will be presented.
22. Quantum decoherence and entanglement in two-mode open systems
Aurelian Isar
NIPNE, Bucharest, Romania
In the framework of the theory of open systems based on completely positive quantum dynamical semigroups,
we investigate the quantum decoherence and entanglement for a system consisting of two modes embedded
in a thermal environment. Based on the time evolution of the density matrix in coordinate representation, we
determine the degree of quantum decoherence of the considered system. By using the Peres-Simon necessary
and sufficient criterion for separability of two-mode Gaussian states, we also investigate the dynamics of
entanglement in terms of the covariance matrix. Using the upper and lower bounds on the symplectic invariant
obtained in terms of global and marginal purities, we determine the asymptotic Gaussian maximally entangled
mixed states (GMEMS) and the corresponding asymptotic maximal logarithmic negativity, which characterizes
the degree of entanglement of these states.
23. Quantum Monte-Carlo for Non-Markovian dynamics
Guillaume Hupin
GANIL, Caen, France
24. Dissipation in Multidimensional Quantum Tunneling and Sub-barrier Fusion
Baha Balantekin
U-Wisconsin, USA
Abstract to follow
25. The nuclear many-body problem: an open quantum system perspective
Denis Lacroix
GANIL, Caen, France