Strongly correlated manybody systems out of equilibrium: from transient to steady state
03.05.2013 at 10:15
The understanding of the nonequilibrium behavior of strongly correlated quantum many-body systems is a long standing challenge, both in theory as well as in experiments. This talk will focus on two examples: (i) the transient dynamics of impurities in quantum gases and (ii) the nonequilibrium steady state in a correlated electron system.
(i) We outline a program of how to probe quantum impurity problems with ultracold atoms using well established tools from quantum optics . In particular, we reconsider the classic problem of the orthogonality catastrophe and discover new features which could not be observed in previous realizations.
(ii) In the second part of the talk, we present a new numerical approach  that allows to calculate nonequilibrium steady state properties of strongly correlated quantum many-body systems. The approach is formulated in the framework of Keldysh Green's functions and is based on the ideas of dynamical mean-field theory. We apply the presented approach to non-linear transport across a strongly correlated layer described by the fermionic Hubbard model.
 M. Knap, A. Shashi, Y. Nishida, A. Imambekov, D.A. Abanin, E. Demler Phys. Rev. X 2, 041020 (2012).
 E. Arrigoni, M. Knap, and W. von der Linden, Phys. Rev. Lett. 110, 086403 (2013).
A348 - Theresienstr. 37