Scaling the electrical current switching of exchange bias in fully-epitaxial antiferromagnet/ferromagnet bilayers

TL;DR

This study demonstrates how electrical current can manipulate exchange bias in fully-epitaxial antiferromagnet/ferromagnet bilayers, revealing the role of AFM local moments and providing insights for future AFM material control.

Contribution

It systematically compares electrical current switching of exchange bias in Mn-based AFM/ferromagnet bilayers, highlighting the influence of AFM local moments on switching behavior.

Findings

Current pulse can manipulate exchange bias field $H_{ex}$

Exponential decay of $H_{ex}$ with current density

Saturation current density increases with AFM local moment

Abstract

While the electrical current manipulation of antiferromagnets (AFMs) has been demonstrated, the extent of the studied AFM materials has been limited with few systematic experiments and a poor understanding. We compare the electrical current switching of the exchange-bias field ($H_{ex}$) in AFM-Mn$_3A$N/ferromagnet-Co$_3$FeN bilayers. An applied pulse current can manipulate $H_{ex}$ with respect to the current density and FM layer magnetization, which shifts exponentially as a function of the current density. We found that the saturation current density and exponential decay constant $\tau$ increase with the local moment of AFM Mn atoms. Our results highlight the effect of the AFM local moment to electrical current switching of $H_{ex}$, although it has a near-zero net magnetization, and may provide a facile way to explore the electrical current manipulation of AFM materials.