Intrinsic Spin Hall Edges

TL;DR

This paper demonstrates that intrinsic spin Hall currents, which vanish in the bulk, can be detected at the edges of a Rashba spin-orbit coupled system through edge spin accumulation and diffusion into normal regions.

Contribution

It reveals that edge effects enable detection of intrinsic spin Hall currents in systems where bulk currents are absent, clarifying detection methods.

Findings

Spin Hall currents vanish in the bulk but are detectable at edges.

Edge spin accumulation diffuses into normal regions, contributing to spin currents.

Detection of intrinsic spin Hall effects is possible via edge measurements.

Abstract

The prediction of intrinsic spin Hall currents by Murakami \textit{et al.} and Sinova \textit{et al.} raised many questions about methods of detection and the effect of disorder. We focus on a contact between a Rashba type spin orbit coupled region with a normal two-dimensional electron gas and show that the spin Hall currents, though vanishing in the bulk of the sample, can be recovered from the edges. We also show that the current induced spin accumulation in the spin orbit coupled system diffuses into the normal region and contributes to the spin current in the leads.