Temperature dependence of spin depolarization of drifting electrons in n-type GaAs bulks

TL;DR

This study uses Monte Carlo simulations to analyze how temperature and electric fields affect spin relaxation lengths and times of electrons in n-type GaAs, revealing nonmonotonic dependencies.

Contribution

It introduces a detailed Monte Carlo model incorporating intravalley and intervalley scattering to study temperature-dependent spin depolarization in GaAs.

Findings

Spin depolarization lengths vary nonmonotonically with temperature.

Spin relaxation times are influenced by electric field strength.

Temperature and electric field effects are interconnected in spin dynamics.

Abstract

The influence of temperature and transport conditions on the electron spin relaxation in lightly doped n-type GaAs semiconductors is investigated. A Monte Carlo approach is used to simulate electron transport, including the evolution of spin polarization and relaxation, by taking into account intravalley and intervalley scattering phenomena of the hot electrons in the medium. Spin relaxation lengths and times are computed through the D'yakonov-Perel process, which is the more relevant spin relaxation mechanism in the regime of interest (10 < T < 300 K). The decay of the initial spin polarization of the conduction electrons is calculated as a function of the distance in the presence of a static electric field varying in the range 0.1 - 2 kV/cm. We find that the electron spin depolarization lengths and times have a nonmonotonic dependence on both the lattice temperature and the electric field amplitude.