Plasmon dispersion of a two-dimensional electron system with finite layer width

Abstract

Plasmon dispersion of ultralow density two-dimensional electron systems obtained by Hirjibehedin et al. [Phys. Rev. B 65, 161309(R) (2002)] is investigated theoretically. The cancellation of the higher-order nonlocal finite-wave-vector correction and the layer width correction to the plasmon dispersion found by Hwang and Das Sarma [Phys. Rev. B 64, 165409 (2001)] is confirmed analytically within the framework of the self-consistent linear response approximation. If the exchange correlation term calculated by Rajagopal [Phys. Rev. B 15, 4264 (1977)] is added, the obtained theoretical dispersion relation shows excellent quantitative agreement with the zero temperature result experimentally obtained by Hirjibehedin et al.