Spin Hall magnetoresistance and spin Nernst magnetothermopower: role of the inverse spin galvanic effect

TL;DR

This paper investigates how current-induced spin polarizations influence boundary conditions in ferromagnet/normal-metal bilayers, revealing asymmetric effects on spin Hall magnetoresistance and spin Nernst magnetothermopower.

Contribution

It introduces a model using a Rashba 2D electron gas to quantify the impact of spin polarization on boundary conditions and magnetoresistance.

Findings

Spin Hall magnetoresistance depends asymmetrically on magnetization direction.

Current-induced spin polarization significantly affects boundary conditions.

The system exhibits non-trivial boundary condition effects due to spin polarization.

Abstract

In ferromagnet/normal-metal bilayers, the sensitivity of the spin Hall magnetoresistance and the spin Nernst magnetothermopower to the boundary conditions at the interface is of central importance. In general, such boundary conditions can be substantially affected by current-induced spin polarizations. In order to quantify the role of the latter, we consider a Rashba two-dimensional electron gas with a ferromagnet attached to one side of the system. The geometry of such a system maximizes the effect of current-induced spin polarization on the boundary conditions, and the spin Hall magnetoresistance is shown to acquire a non-trivial and asymmetric dependence on the magnetization direction of the ferromagnet.