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Spectral moment sum rules for strongly correlated electrons in time-dependent electric fields

V. M. Turkowski·J. K. Freericks
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Abstract

We derive exact operator average expressions for the first two spectral moments of nonequilibrium Green's functions for the Falicov-Kimball model and the Hubbard model in the presence of a spatially uniform, time-dependent electric field. The moments are similar to the well-known moments in equilibrium, but we extend those results to systems in arbitrary time-dependent electric fields. Moment sum rules can be employed to estimate the accuracy of numerical calculations; we compare our theoretical results to numerical calculations for the nonequilibrium dynamical mean-field theory solution of the Falicov-Kimball model at half-filling.

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V. M. Turkowski, J. K. Freericks. 2005-11-02. Spectral moment sum rules for strongly correlated electrons in time-dependent electric fields. https://doi.org/10.1103/physrevb.73.209902

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