Topological Aspects of Antiferromagnets

TL;DR

This review explores how topological phenomena in antiferromagnets lead to novel electronic, magnetic, and magnonic behaviors, highlighting their potential for advanced low-power spintronic applications.

Contribution

It provides a comprehensive overview of recent discoveries linking topology to antiferromagnetic properties and discusses new mechanisms and future directions in the field.

Findings

Topological effects cause anomalous Hall phenomena in antiferromagnets.

Emergence of homochiral magnetic entities like skyrmions.

Potential for low-power spintronic devices using topological antiferromagnets.

Abstract

The long fascination antiferromagnetic materials have exerted on the scientific community over about a century has been entirely renewed recently with the discovery of several unexpected phenomena including various classes of anomalous spin and charge Hall effects and unconventional magnonic transport, but also homochiral magnetic entities such as skyrmions. With these breakthroughs, antiferromagnets standout as a rich playground for the investigation of novel topological behaviors, and as promising candidate materials for disruptive low-power microelectronic applications. Remarkably, the newly discovered phenomena are all related to the topology of the magnetic, electronic or magnonic ground state of the antiferromagnets. This review exposes how non-trivial topology emerges at different levels in antiferromagnets and explores the novel mechanisms that have been discovered recently. We also discuss how novel classes of quantum magnets could enrich the currently expanding field of antiferromagnetic spintronics and how spin transport can in turn favor a better understanding of exotic quantum excitations.