Effect of Screening on Spin Polarization in a Two-Dimensional Electron Gas

TL;DR

This paper explains how screening of Coulomb interactions influences spin polarization and susceptibility in a two-dimensional electron gas, accounting for experimental observations and the potential for spontaneous polarization at low densities.

Contribution

It demonstrates that screening effects are key to understanding spin polarization behavior and susceptibility in 2D electron gases, providing a theoretical explanation for experimental results.

Findings

Screening explains the dependence of critical magnetic field Bc on electron density.

Screening affects the spin susceptibility of the electron gas.

Spontaneous full spin polarization at low densities depends critically on screening.

Abstract

The experimentally observed amazing dependence of a critical magnetic field Bc of a full field-induced spin polarization and a spin susceptibility of a two-dimensional electron gas on the electron density can be explained by screening of the Coulomb potential. The possibility of spontaneous full spin polarization expected at lower electron densities also crucially depends on screening.