Enhanced spin Hall effect in semiconductor heterostructures with artificial potential

TL;DR

This paper presents a theoretical study of an enhanced extrinsic spin Hall effect in semiconductor heterostructures, showing how artificial, tunable potentials can significantly boost spin current polarization through resonant scattering.

Contribution

It introduces a phase shift formulation for SHE in 2D electron gases and demonstrates how artificial potentials can be tuned to enhance spin current polarization in a three-terminal device.

Findings

Resonant scattering significantly enhances SHE.

Artificial potentials can be electrically tuned for optimal effect.

Potential to produce highly polarized spin currents (>50%).

Abstract

We theoretically investigate an extrinsic spin Hall effect (SHE) in semiconductor heterostructures due to the scattering by an artificial potential created by antidot, STM tip, etc. The potential is electrically tunable. First, we formulate the SHE in terms of phase shifts in the partial wave expansion for two-dimensional electron gas. The effect is significantly enhanced by the resonant scattering when the attractive potential is properly tuned. Second, we examine a three-terminal device including an antidot, which possibly produces a spin current with polarization of more than 50%.