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Nonlinear screening in two-dimensional electron gases

E. Zaremba·I. Nagy·P. M. Echenique
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Abstract

We have performed self-consistent calculations of the nonlinear screening of a point charge Z in a two-dimensional electron gas using a density functional theory method. We find that the screened potential for a Z=1 charge supports a bound state even in the high density limit where one might expect perturbation theory to apply. To explain this behaviour, we prove a theorem to show that the results of linear response theory are in fact correct even though bound states exist.

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E. Zaremba, I. Nagy, P. M. Echenique. 2002-08-21. Nonlinear screening in two-dimensional electron gases. https://doi.org/10.1103/physrevlett.90.046801

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