Angular dependence of domain wall resistivity in artificial magnetic domain structures

TL;DR

This study investigates how the electrical resistance caused by magnetic domain walls in artificial structures depends on the angle of the walls, confirming theoretical models and providing quantitative estimates of spin-dependent resistivities.

Contribution

The paper demonstrates the angular dependence of domain wall resistivity in artificial magnetic structures and validates the Levy-Zhang theory with experimental data.

Findings

Resistivity tensor accurately describes angular dependence.

Measured spin resistivity ratio rho-down/rho-up~5.5.

Intrinsic domain wall magnetoresistance confirmed.

Abstract

We exploit the ability to precisely control the magnetic domain structure of perpendicularly magnetized Pt/Co/Pt trilayers to fabricate artificial domain wall arrays and study their transport properties. The scaling behaviour of this model system confirms the intrinsic domain wall origin of the magnetoresistance, and systematic studies using domains patterned at various angles to the current flow are excellently described by an angular-dependent resistivity tensor containing perpendicular and parallel domain wall resistivities. We find that the latter are fully consistent with Levy-Zhang theory, which allows us to estimate the ratio of minority to majority spin carrier resistivities, rho-down/rho-up~5.5, in good agreement with thin film band structure calculations.