Spin relaxation and antisymmetric exchange in n-doped III-V semiconductor

TL;DR

This paper investigates the role of Dzyaloshinskii-Moriya interaction in spin relaxation of n-doped GaAs near the metal-insulator transition, deriving a Hamiltonian and analyzing its impact on spin dephasing.

Contribution

The authors derive the correct spin Hamiltonian for localized electrons and evaluate its effect on spin relaxation, challenging previous assumptions about the dominant relaxation mechanism.

Findings

Dzyaloshinskii-Moriya interaction alone cannot account for observed spin relaxation times.

The derived Hamiltonian provides a more accurate description of spin dynamics in n-doped GaAs.

The proposed mechanism is insufficient to explain experimental data.

Abstract

Recently K. Kavokin [Phys. Rev. B 64, 075305 (2001)] suggested that the Dzyaloshinskii-Moriya interaction between localized electrons governs slow spin relaxation in $n$-doped GaAs in the regime close to the metal-insulator transition. We derive the correct spin Hamiltonian and apply it to the determination of spin dephasing time using the method of moments expansion. We argue that the proposed mechanism is insufficient to explain the observed values of the spin relaxation time.