Intrinsic vs. Extrinsic Spin Currents. Old Ideas in a New Light

TL;DR

This paper investigates electron spin dynamics with Rashba spin-orbit interaction and disorder, revealing that spin current vanishes under certain conditions and exploring related magnetotransport phenomena.

Contribution

It provides a new perspective on spin currents by showing their null value in the Born approximation and discusses related magnetotransport effects.

Findings

Spin current is zero in the Born approximation regardless of parameters.

Negative magnetoresistance observed in the presence of spin-orbit coupling.

Negative charge Hall effect occurs with spin-orbit interaction.

Abstract

We have described the electron spin dynamics in the presence of Rashba spin- orbit interaction and disorder using the spin-density matrix method. We showed that in the Born approximation in the scattering amplitude the spin current is zero for an arbitrary ratio of the spin-orbit splitting and the scattering rate and for an arbitrary disorder potential. We also describe some magnetotransport phenomena such as negative magnetoresistance and a negative charge Hall effect which occur in the presence of spin-orbit coupling.