title: Real-time kadanoff-baym approach to plasma oscillations in a correlated electron gas.
abstract: A nonequilibrium Green's functions approach to the collective response of correlated Coulomb systems at finite temperatures is presented. It is shown that solving Kadanoff-Baym-type equations of motion for the two-time correlation functions including the external perturbing field allows one to compute the plasmon spectrum with collision effects in a systematic and consistent way. The scheme has a "built-in" sum-rule preservation and is simpler to implement numerically than the equivalent equilibrium approach based on the Bethe-Salpeter equation.
authors.affiliation: Fachbereich Physik, Universität Rostock, Universitätsplatz 3, D-18051 Rostock, Germany.
authors.forename: N H
authors.initials: NH
authors.lastname: Kwong
authors.forename: M
authors.initials: M
authors.lastname: Bonitz