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arXiv · 2508.13585

Deterministic N\'eel vector switching of altermagnets via magnetic octupole torque

Seungyun Han·Insu Baek·Kyoung-Whan Kim·Hyun-Woo Lee·Suik Cheon
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Abstract

Altermagnets have recently emerged as promising materials for next-generation spintronic devices. For their device applications, realizing a single-domain configuration is essential but remains challenging. We theoretically consider injecting magnetic multipoles into altermagnets, which can be achieved by applying an in-plane current to an altermagnet/normal metal bilayer. We demonstrate for $d$-wave altermagnets that the torque generated by the magnetic octupole injection can achieve magnetic-field-free deterministic switching of the altermagnets' N\'eel vector and transform their multidomain configurations into a single domain. This method allows the switching in diverse altermagnets, thereby facilitating their device applications and fundamental studies. This work also exemplifies the usefulness of magnetic multipole currents.

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Seungyun Han, Insu Baek, Kyoung-Whan Kim, Hyun-Woo Lee, Suik Cheon. 2025-08-19. Deterministic N\'eel vector switching of altermagnets via magnetic octupole torque. https://doi.org/10.1002/smll.202511790

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