Electron and Spin Correlations in Semiconductor Heterostructures: Quantum Singwi-Tosi-Land-Sjolander Theory

TL;DR

This paper uses the quantum Singwi-Tosi-Land-Sjolander theory to analyze many-body effects in quasi-two-dimensional electron liquids in semiconductor heterostructures, highlighting the impact of layer thickness on correlation functions and dielectric properties.

Contribution

The study extends the QSTLS theory to include layer thickness effects in Q2D electron liquids, providing detailed calculations of structure factors, pair distribution functions, and dielectric functions.

Findings

Finite thickness significantly affects the dielectric function.

QSTLS results differ notably from STLS at intermediate wave numbers.

Calculated correlation functions agree with previous 2D electron liquid studies.

Abstract

We apply the quantum Singwi-Tosi-Land-Sjolander (QSTLS) theory for a study of many-body effects in the quasi-two-dimensional (Q2D) electron liquid (EL) in GaAs/AlxGa1-xAs heterojunctions. The effect of the layer thickness is included through a variational approach. We have calculated the density, spin-density static structure factors, spin-dependent pair distribution functions (PDF) and compared our results with those of two-dimensional (2D) EL given in earlier papers. Using the static structure factors (SSF) we have calculated various dynamic correlation functions such as spin-dependent local-field factors (LFF) and effective potentials of the Q2D EL. We have also calculated the inverse static dielectric function of the 2D and Q2D EL using different approximations. We find that the effect of finite thickness on the dielectric function is remarkable and at the intermediate values of wave number q there is a significant difference between the QSTLS and STLS results.