Influences of spin accumulation on the intrinsic spin Hall effect in two dimensional electron gases with Rashba spin-orbit coupling

TL;DR

This paper studies how spin accumulation at sample edges affects the intrinsic spin Hall effect in 2D electron gases with Rashba coupling, revealing non-universal spin Hall conductivity due to boundary-induced spin accumulation.

Contribution

It provides a detailed analysis of the impact of boundary-induced spin accumulation on the intrinsic spin Hall effect in narrow 2D electron gas strips with Rashba coupling.

Findings

Spin accumulation occurs near sample edges due to the spin Hall current.

Spin accumulation causes the spin Hall conductivity to deviate from its universal value.

Boundary effects significantly influence the intrinsic spin Hall effect in narrow samples.

Abstract

In a two dimensional electron gas with Rashba spin-orbit coupling, the external electric field may cause a spin Hall current in the direction perpendicular to the electric field. This effect was called the intrinsic spin Hall effect. In this paper, we investigate the influences of spin accumulation on this intrinsic spin Hall effect. We show that due to the existence of boundaries in a real sample, the spin Hall current generated by the intrinsic spin Hall effect will cause spin accumulation near the edges of the sample, and in the presence of spin accumulation, the spin Hall conductivity will not have a universal value. The influences of spin accumulation on the intrinsic spin Hall effect in narrow strips of two dimensional electron gases with Rashba spin-orbit coupling are investigated in detail.