Dynamic response of a strongly perturbed electron gas

Abstract

The dynamic response of an electron gas strongly perturbed by an impurity is calculated using density functional theory and many-body linear response theory. We find that the piling up of charge induced by the impurity significantly modifies electron dynamics in the vicinity of the impurity and the response of the system to localized external perturbations. Our results show the important local effects that the nonlinear screening of impurities introduce in the dynamic response of metallic systems. © 2003 The American Physical Society.