Ultrafast extrinsic spin-Hall currents

TL;DR

This paper proposes a phenomenological model for ultrafast extrinsic spin-Hall currents generated by skew scattering in quantum wells, where optically injected charge or spin currents induce measurable spin or charge accumulations.

Contribution

It introduces a new model describing how optical injection can generate ultrafast extrinsic spin-Hall currents in quantum well structures.

Findings

Injected charge current induces spin current via spin-Hall effect

Injected spin current induces charge current via spin-Hall effect

Spin or charge accumulation can be detected optically

Abstract

We consider the possibility of ultrafast extrinsic spin-Hall currents, generated by skew scattering following the optical injection of charge or pure spin currents. We propose a phenomenological model for this effect in quantum well structures. An injected charge current leads to a spin-Hall-induced pure spin current, and an injected pure spin current leads to a spin-Hall-induced charge current. The resulting spin or charge accumulation can be measured optically.