Spin relaxation time, spin dephasing time and ensemble spin dephasing time in $n$-type GaAs quantum wells

TL;DR

This paper studies spin relaxation and dephasing times in n-type GaAs quantum wells, showing they are identical due to short correlation times and that Coulomb scattering suppresses inhomogeneous broadening.

Contribution

The work provides a full microscopic calculation of spin relaxation and dephasing times, revealing their equivalence and the role of Coulomb scattering in GaAs quantum wells.

Findings

T1, T2, and T2* are identical in the system.

Coulomb scattering suppresses inhomogeneous broadening.

Spin relaxation and dephasing are governed by scattering processes.

Abstract

We investigate the spin relaxation and spin dephasing of $n$-type GaAs quantum wells. We obtain the spin relaxation time $T_1$, the spin dephasing time $T_2$ and the ensemble spin dephasing time $T_2^{\ast}$ by solving the full microscopic kinetic spin Bloch equations, and we show that, analogous to the common sense in an isotropic system for conduction electrons, $T_1$, $T_2$ and $T_2^{\ast}$ are identical due to the short correlation time. The inhomogeneous broadening induced by the D'yakonov-Perel term is suppressed by the scattering, especially the Coulomb scattering, in this system.