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arXiv · 1210.4926

Impurity model for non-equilibrium steady states

Camille Aron·Cedric Weber·Gabriel Kotliar
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Abstract

We propose an out-of-equilibrium impurity model for the dynamical mean-field description of the Hubbard model driven by a finite electric field. The out-of-equilibrium impurity environment is represented by a collection of equilibrium reservoirs at different chemical potentials. We discuss the validity of the impurity model and propose a non-perturbative method, based on a quantum Monte Carlo solver, which provides the steady-state solutions of the impurity and original lattice problems. We discuss the relevance of this approach to other non-equilibrium steady-state contexts.

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Camille Aron, Cedric Weber, Gabriel Kotliar. 2012-10-17. Impurity model for non-equilibrium steady states. https://doi.org/10.1103/physrevb.87.125113

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