Nonlinear magnetotransport in dual spin valves

TL;DR

This paper presents a phenomenological model explaining nonlinear magnetoresistance in dual spin valves, incorporating current-dependent resistance and spin asymmetry parameters based on a modified Valet-Fert approach.

Contribution

It introduces a novel nonlinear model for dual spin valves that accounts for current-dependent resistance and spin asymmetry parameters, explaining recent experimental observations.

Findings

Model successfully reproduces nonlinear magnetoresistance features.

Accounts for dependence of resistance on spin accumulation and charge current.

Aligns with recent experimental measurements of dual spin valves.

Abstract

Recent experimental measurements of magnetoresistance in dual spin valves [A. Aziz et al., Phys. Rev. Lett. 103, 237203 (2009)] reveal some nonlinear features of transport, which have not been observed in other systems. We propose a phenomenological model describing current-dependent resistance (and giant magnetoresistance) in double spin valves. The model is based on a modified Valet-Fert approach, and takes into account the dependence of bulk/interface resistance and bulk/interface spin asymmetry parameters for the central magnetic layer on spin accumulation, and consequently on charge current. Such a nonlinear model accounts for recent experimental observations.