Effect of Singwi-Tosi-Land-Sj\"{o}lander local field correction on spin relaxation in $n$-type GaAs quantum wells at low temperature

TL;DR

This study investigates how the Singwi-Tosi-Land-Sj"{o}lander local field correction influences spin relaxation times in n-type GaAs quantum wells at low temperatures, revealing its moderating effects on Coulomb interactions and spin dynamics.

Contribution

It introduces a self-consistent numerical method to incorporate the local field correction into kinetic spin Bloch equations for quantum wells.

Findings

Local field correction modifies spin relaxation times depending on scattering regime.

At high spin polarization, the correction reduces the Hartree-Fock term, affecting relaxation.

The impact of the correction varies with temperature, electron density, and well width.

Abstract

We study the effect of the Singwi-Tosi-Land-Sj\"{o}lander local field correction on spin relaxation/dephasing in $n$-type GaAs quantum wells at low temperature by constructing and numerically solving the kinetic spin Bloch equations. We calculate the local field factor $G(q)$ in quantum wells by numerically solving three equations which link the local field factor, the structure factor, and the dielectric function, self-consistently. Such a correction reduces both the electron-electron Coulomb scattering and the Coulomb Hartree-Fock term. We compare the spin relaxation times with and without this correction under different conditions such as temperature, electron density, well width and spin polarization. We find that this correction leads to a decrease/increase of the spin relaxation time in the strong/weak scattering limit. At high spin polarization, it reduces the Hartree-Fock term and consequently tends to decrease the spin relaxation time. The modification of the spin relaxation time by the local field correction is more or less moderate either due to the coexistence of scattering other than the Coulomb scattering at low spin polarization and/or due to the competing effects from the Coulomb scattering and the Coulomb Hartree-Fock term at high polarization.