Theory of spin-Hall transport of heavy holes in semiconductor quantum wells

TL;DR

This paper theoretically investigates the spin-Hall effect of heavy holes in semiconductor quantum wells, concluding that a steady-state spin-Hall current does not exist under DC electric fields when using a proper spin current definition.

Contribution

It provides a revised theoretical analysis showing the absence of steady-state spin-Hall currents in heavy-hole systems with Rashba coupling, contrasting previous results.

Findings

Steady-state spin-Hall current is absent under DC fields.

AC fields can induce a spin-Hall effect in these systems.

Proper spin current definition alters previous conclusions.

Abstract

Based on a proper definition of the spin current, we investigate the spin-Hall effect of heavy holes in narrow quantum wells in the presence of Rashba spin-orbit coupling by using a spin-density matrix approach. In contrast to previous results obtained on the basis of the conventional definition of the spin current, we arrive at the conclusion that an electric-field-induced steady-state spin-Hall current does not exist in both, pure and disordered infinite samples. Only an ac field can induce a spin-Hall effect in such systems.