Nanoscale mechanics of antiferromagnetic domain walls

TL;DR

This study investigates the nanoscale mechanics of antiferromagnetic domain walls in Cr$_2$O$_3$, demonstrating their manipulation via engineered energy landscapes and revealing their elastic properties, which could enable new memory devices.

Contribution

It provides the first detailed experimental analysis of individual antiferromagnetic domain walls and their interaction with topography at the nanoscale.

Findings

Demonstrated control of antiferromagnetic DWs using engineered topography.

Revealed that DW interactions are governed by elastic properties.

Proposed a new memory architecture based on DW manipulation.

Abstract

Antiferromagnets offer remarkable promise for future spintronics devices, where antiferromagnetic order is exploited to encode information. The control and understanding of antiferromagnetic domain walls (DWs) - the interfaces between domains with differing order parameter orientations - is a key ingredient for advancing such antiferromagnetic spintronics technologies. However, studies of the intrinsic mechanics of individual antiferromagnetic DWs remain elusive since they require sufficiently pure materials and suitable experimental approaches to address DWs on the nanoscale. Here we nucleate isolated, 180{\deg} DWs in a single-crystal of Cr$_2$O$_3$, a prototypical collinear magnetoelectric antiferromagnet, and study their interaction with topographic features fabricated on the sample. We demonstrate DW manipulation through the resulting, engineered energy landscape and show that the observed interaction is governed by the DW's elastic properties. Our results advance the understanding of DW mechanics in antiferromagnets and suggest a novel, topographically defined memory architecture based on antiferromagnetic DWs.