Signatures of spin-preserving symmetries in two-dimensional hole gases

TL;DR

This paper explores how spin-preserving symmetries influence conductance in disordered 2D hole gases, extending models beyond axial approximation to identify exact symmetries affecting spin transport.

Contribution

It introduces an extended model for 2D hole gases that reveals an exact spin-preserving symmetry similar to electrons, analyzing its effects on localization and spin transmission.

Findings

Identifies an exact spin-preserving symmetry in heavy-hole subbands.

Shows crossover from weak antilocalization to weak localization.

Demonstrates impact of extrinsic spin-orbit interaction on conductance.

Abstract

We investigate ramifications of the persistent spin helix symmetry in two-dimensional hole gases in the conductance of disordered mesoscopic systems. To this end we extend previous models by going beyond the axial approximation for III-V semiconductors. For heavy-hole subbands we identify an exact spin-preserving symmetry analogous to the electronic case by analyzing the crossover from weak antilocalization to weak localization and spin transmission as a function of extrinsic spin-orbit interaction strength.