Domain-wall resistance in ferromagnetic (Ga,Mn)As

TL;DR

This paper investigates the resistance caused by domain walls in (Ga,Mn)As, distinguishing between extrinsic effects from Hall field polarity changes and intrinsic effects related to disorder-induced spin misalignment.

Contribution

It provides a quantitative analysis of extrinsic and intrinsic domain-wall resistance contributions in (Ga,Mn)As with perpendicular magnetic anisotropy, highlighting the dominant disorder-induced intrinsic effects.

Findings

Extrinsic resistance explained by Hall field polarity change.

Intrinsic resistance an order of magnitude larger than anisotropic magnetoresistance.

Intrinsic resistance linked to disorder-induced spin misstracing.

Abstract

A series of microstructures designed to pin domain-walls (DWs) in (Ga,Mn)As with perpendicular magnetic anisotropy has been employed to determine extrinsic and intrinsic contributions to DW resistance. The former is explained quantitatively as resulting from a polarity change in the Hall electric field at DW. The latter is one order of magnitude greater than a term brought about by anisotropic magnetoresistance and is shown to be consistent with disorder-induced misstracing of the carrier spins subject to spatially varying magnetization.