Electron correlations in inversion layers

Abstract

The two-dimensional electron gas (2DEG) is a widely used model for the electrons in the inversion layer of certain MOSFET devices. The sensitivity of a number of physical quantities of the 2DEG to a proper treatment of many-body effects has been examined. This was achieved by calculating the plasmon dispersion, pair correlation function, exchange and correlation energy and the self-energy at the Fermi level using three different approximations to the many-body problem, namely: (i) the RPA; (ii) the Hubbard approximation (HA); and (iii) the self-consistent STLS approximation of Singwi et al. (1968). The RPA and HA were found to be less satisfactory approximations for a 2DEG than for a 3DEG.