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Real-time Kadanoff-Baym approach to plasma oscillations in a correlated electron gas

N. -H. Kwong·M. Bonitz
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Abstract

A nonequilibrium Green's functions approach to the collective response of correlated Coulomb systems at finite temperature is presented. It is shown that solving Kadanoff-Baym type equations of motion for the two-time correlation functions with the external perturbing field included allows to compute the plasmon spectrum with collision effects in a systematic and consistent way. The scheme has ``built-in'' sum rule preservation and is simpler to implement numerically than the equivalent equilibrium approach based on the Bethe-Salpeter equation.

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N. -H. Kwong, M. Bonitz. 1999-12-03. Real-time Kadanoff-Baym approach to plasma oscillations in a correlated electron gas. https://doi.org/10.1103/physrevlett.84.1768

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