Spin relaxation due to electron-electron magnetic interaction in high Lande g-factor semiconductors

TL;DR

This paper studies how electron-electron magnetic interactions influence spin relaxation in high g-factor semiconductors, revealing significant effects at high densities and highlighting a general relaxation mechanism.

Contribution

It introduces a Monte Carlo method incorporating spin density matrix to analyze magnetic interactions' impact on spin relaxation in high g-factor materials.

Findings

Magnetic interaction reduces spin relaxation length by up to 50% at high densities.

Magnetic interaction is negligible at low densities.

Wave vector dependent magnetic fields suppress decoherence in Dyakonov-Perel mechanism.

Abstract

We investigate spin transport in InSb/InAlSb heterostructure using the Monte Carlo approach, generalized by including density matrix description of spin for taking spin dynamics into account. In addition to the dominant Dyakonov-Perel (DP) mechanism for spin control and relaxation, we consider magnetic interaction between electrons which assumes importance due to high electronic Lande g-factor in the material. It is found that while the effect of magnetic interaction is not important at low densities, it reduces the spin relaxation length by as much as 50% at higher densities. We also present a calculation which elucidates the suppression of decoherence attributed to wave vector dependent magnetic field in the DP relaxation mechanism. We note that magnetic interaction is a general relaxation mechanism which may assume importance in materials with high electronic Lande g-factor.