Universal Relationship Between Giant Magnetoresistance and Anisotropic Magnetoresistance in Spin Valve Multilayers

TL;DR

This study reveals a universal relationship between giant magnetoresistance and anisotropic magnetoresistance in spin valve multilayers, highlighting the role of bulk scattering in GMR through experimental measurements and Boltzmann transport analysis.

Contribution

It establishes a universal correlation between GMR and AMR in spin valves and emphasizes the significance of bulk scattering effects in GMR behavior.

Findings

GMR difference shows universal behavior as a function of GMR

Bulk scattering is crucial for understanding GMR

Experimental results align with Boltzmann transport theory

Abstract

We measure the giant magnetoresistance (GMR) with the current both parallel and perpendicular to the direction of the magnetization in the ferromagnetic (FM) layers and thus probe the anisotropy of the effective mean free paths for the spin-up and spin-down electrons, seen in the anisotropic magnetoresistance. We find that the difference of the GMR in the two configurations, when expressed in terms of the sheet conductance, displays a nearly universal behavior as a function of GMR. On interpreting the results within the Boltzmann transport formalism we demonstrate the importance of bulk scattering for GMR.