Hole spin relaxation in $p$-type GaAs quantum wires

TL;DR

This study explores how quantum-wire size, temperature, hole density, and initial polarization affect spin relaxation times in p-type GaAs quantum wires, revealing complex dependencies and the significant role of inter-subband scattering.

Contribution

It provides a detailed numerical analysis of spin relaxation in p-type GaAs quantum wires, highlighting the influence of quantum-wire size and subband structure on relaxation dynamics.

Findings

Spin relaxation time varies with wire size, temperature, and hole density.

Inter-subband scattering significantly impacts spin relaxation.

Spin relaxation properties differ from bulk and quantum well cases.

Abstract

We investigate the spin relaxation of $p$-type GaAs quantum wires by numerically solving the fully microscopic kinetic spin Bloch equations. We find that the quantum-wire size influences the spin relaxation time effectively by modulating the energy spectrum and the heavy-hole--light-hole mixing of wire states. The effects of quantum-wire size, temperature, hole density, and initial polarization are investigated in detail. We show that, depending on the situation, the spin relaxation time can either increase or decrease with hole density. Due to the different subband structure and effects arising from spin-orbit coupling, many spin-relaxation properties are quite different from those of holes in the bulk or in quantum wells, and the inter-subband scattering makes a marked contribution to the spin relaxation.