Defect-driven antiferromagnetic domain walls in CuMnAs films

TL;DR

This study uncovers how nanoscale twin defects in CuMnAs films influence antiferromagnetic domain walls, highlighting defect control as key for optimizing spintronic device performance.

Contribution

It reveals the microscopic role of nanoscale twin defects in shaping AF domain walls in CuMnAs, combining microscopy, diffraction, and simulations.

Findings

Twin defects determine AF domain wall locations and orientations

Nanoscale defects dominate the AF domain structure

Results suggest defect engineering can optimize device performance

Abstract

Efficient manipulation of antiferromagnetic (AF) domains and domain walls has opened up new avenues of research towards ultrafast, high-density spintronic devices. AF domain structures are known to be sensitive to magnetoelastic effects, but the microscopic interplay of crystalline defects, strain and magnetic ordering remains largely unknown. Here, we reveal, using photoemission electron microscopy combined with scanning X-ray diffraction imaging and micromagnetic simulations, that the AF domain structure in CuMnAs thin films is dominated by nanoscale structural twin defects. We demonstrate that microtwin defects, which develop across the entire thickness of the film and terminate on the surface as characteristic lines, determine the location and orientation of 180 degree and 90 degree domain walls. The results emphasize the crucial role of nanoscale crystalline defects in determining the AF domains and domain walls, and provide a route to optimizing device performance.