Local setting of spin textures in a granular antiferromagnet

TL;DR

This paper introduces a novel atomistic simulation method to nucleate and stabilize local spin textures in antiferromagnetic grains, advancing the control of magnetic order for spintronic applications.

Contribution

It demonstrates a thermal cycling technique to set localized spin textures in antiferromagnetic grains via exchange bias with a ferromagnet, a new approach for controlling antiferromagnetic order.

Findings

Local spin textures can be nucleated and stabilized in $\gamma$-IrMn$_3$ grains.

Material parameters influence the efficiency and characteristics of the set textures.

The method enables potential development of antiferromagnetic spintronic devices with complex spin states.

Abstract

Controlling the magnetic order of antiferromagnets is challenging due to their vanishing net magnetization. For this reason, the study of local spin textures in antiferromagnets is restricted by the difficulty in nucleating such states. Here, using atomistic simulations we demonstrate a method for nucleating localized spin textures in the grains of thin film antiferromagnet, $\gamma$-IrMn$_3$. Utilising the exchange bias coupling between a ferromagnet and an antiferromagnet, we set the spin texture in the latter from a predefined spin texture in the former by means of a thermal cycling procedure. The local textures set in the antiferromagnetic grains are shown to be stable against field perturbations. We also discuss how various material parameters affect the efficiency of the setting and the characteristics of these set textures. The setting of antiferromagnetic spin textures provides a potential route to antiferromagnetic spintronic devices with non-collinear spin states such as skyrmions, bubbles and domain walls.