Coulomb Effects on the Magnetoconductance of a Two-Dimensional Electron Gas in a Lateral Superlattice: A Screened Hartree-Fock Calculation

TL;DR

This paper investigates how Coulomb interactions influence the magnetoconductance of a two-dimensional electron gas in a lateral superlattice, using a screened Hartree-Fock approach to analyze experimental phenomena like Shubnikov-de Haas peaks.

Contribution

It introduces a screened Hartree-Fock calculation to accurately model electron-electron interactions in a 2D electron gas under magnetic fields and periodic potentials.

Findings

Reveals internal structure of Shubnikov-de Haas peaks.

Shows electron-electron interactions lead to exchange-enhanced spin splitting.

Describes formation of compressible strips in the system.

Abstract

We calculate the magnetoconductivity tensor of a 2D electron gas in a 1D periodic potential and quantising magnetic fields. We study the internal structure of the Shubnikov-de Haas peaks and analyse recent experimental results. The electron-electron interaction is accounted for within a screened Hartree-Fock approximation (HFA), which describes both compressible strips and an exchange-enhanced spin splitting, unlike the Hartree and the standard HFA.