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Nonequilibrium dynamical mean-field theory of a strongly correlated system

P. Schmidt·H. Monien
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Abstract

We present a generalized dynamical mean-field approach for the nonequilibrium physics of a strongly correlated system in the presence of a time-dependent external field. The Keldysh Green's function formalism is used to study the nonequilibrium problem. We derive a closed set of self-consistency equations in the case of a driving field with frequency Omega and wave vector q. We present numerical results for the local frequency-dependent Green's function and the self-energy for different values of the field amplitude in the case of a uniform external field using the iterated perturbation theory. In addition, an expression for the frequency-dependent optical conductivity of the Hubbard model with a driving external field is derived.

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P. Schmidt, H. Monien. 2002-02-04. Nonequilibrium dynamical mean-field theory of a strongly correlated system. https://arxiv.org/abs/cond-mat/0202046

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