Topological Spin Textures in a Non-Collinear Antiferromagnet System.

Abstract

Topologically protected magnetic "whirls" such as skyrmions in antiferromagnetic materials have recently attracted extensive interests due to their nontrivial band topology and potential application in antiferromagnetic spintronics. However, the room-temperature skyrmions in natural metallic antiferromagnetic materials with merit of probably conveniently electrical manipulation have not been reported. Here, we realize room-temperature skyrmions in a non-collinear antiferromagnet Mn3 Sn capped with a Pt overlayer. The evolution of spin textures from coplanar inverted triangular structures to Bloch-type skyrmions is achieved via tuning the magnitude of interfacial Dzyaloshinskii - Moriya interaction. Beyond that, the temperature can induce an unconventional transition from skyrmions to antiferromagnetic meron-like spin textures at approximately 220 K in our Mn3 Sn/Pt samples. Combining with the theoretical calculations, we find the transition is originated from the temperature dependence of antiferromagnetic exchange interaction between kagome sublayers within the Mn3 Sn crystalline unitcell. Our findings open the avenue for the development of topological spin-swirling-based antiferromagnetic spintronics. This article is protected by copyright. All rights reserved.