Field of Expertise: Advanced Material Science
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Field of Expertise: Advanced Material Science | |
Steady-state characteristics of correlated quantum many-body systems out of equilibrium: applications to quantum dots and molecular junctions The theoretical understanding of the non-equilibrium behavior of strongly correlated quantum many-body systems is a long standing challenge, which has become increasingly relevant with the progress made in the fields of molecular-and nano- electronics, spintronics, spectroscopy or quantum optics and simulation. In this talk we discuss the physics of nanoscopic devices like quantum dots and molecular junctions under bias voltage and magnetic fields. The effects of strong interactions between the constituent electrons prohibit a straight forward theoretical understanding. Therefore special techniques have to be developed and applied to deal on the one hand with electronic correlations. On the other hand one would like to treat the non-equilibrium situation in the thermodynamic limit and exchange particles with a bath and/or dissipate energy. We discuss physical systems in linear response theory [1] and using a quantum mechanical time evolution using matrix product states techniques [2]. To capture the steady-state physics, the development of non-equilibrium cluster perturbation theory [3], and its variational improvement, the non-equilibrium variational cluster approach [4] as well as non-equilibrium dynamical mean field theory [5] will be presented. Obtained physical phenomena will be discussed in the context of condensed matter systems. |