Nonuniversality of the intrinsic inverse spin-Hall effect in diffusive systems

TL;DR

This paper investigates how the inverse spin-Hall effect in two-dimensional electron gases varies depending on the origin of the spin current, revealing nonuniversality and different behaviors for inhomogeneous versus homogeneous spin currents.

Contribution

It demonstrates that the inverse spin-Hall effect's magnitude depends on the spin current's origin, challenging the assumption of universality in diffusive systems with spin-orbit interactions.

Findings

Finite inverse spin-Hall effect for inhomogeneous spin density diffusion.

Zero inverse spin-Hall effect for homogeneous spin currents with Rashba interaction.

The effect's dependence on the origin of the spin current.

Abstract

We studied the electric current induced in a two-dimensional electron gas by the spin current, in the presence of Rashba and cubic Dresselhaus spin-orbit interactions. We found out that the factor relating these currents is not universal, but rather depends on the origin of the spin current. Drastic distinction has been found between two cases: the spin current created by diffusion of an inhomogeneous spin density, and the pure homogeneous spin current. We found out that in the former case the ISHE electric current is finite, while it turns to zero in the latter case, if the spin-orbit coupling is represented by Rashba interaction.