Supercurrent-Driven Néel Torque in Superconductor/Altermagnet Hybrids

Hamed Vakili; Moaz Ali; Igor Žutić; Alexey A. Kovalev

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arXiv · 2603.22243

Supercurrent-Driven Néel Torque in Superconductor/Altermagnet Hybrids

Hamed Vakili·Moaz Ali·Igor Žutić·Alexey A. Kovalev

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Abstract

We predict a supercurrent-driven Néel spin-orbit torque in a superconductor/$d$-wave altermagnet heterostructure, associated with the emergence of spin-triplet correlations. The effect can be understood as a consequence of the supercurrent-induced spin polarization, owing to the interplay between spin orbit coupling and momentum-dependent spin splitting, as found, for example, in altermagnets. Remarkably, the supercurrent can be tuned by the Néel-vector direction, and the supercurrent-induced torque can both propel magnetic domain walls and reverse the Néel-vector orientation within a domain wall. These findings establish superconductor/altermagnet heterostructures as a versatile platform for the {supercurrent-driven} control of the Néel vector, with potential applications in racetrack memory, dissipationless superconducting electronics, and unconventional computing.

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Hamed Vakili, Moaz Ali, Igor Žutić, Alexey A. Kovalev. 2026-09-17. Supercurrent-Driven Néel Torque in Superconductor/Altermagnet Hybrids. https://arxiv.org/abs/2603.22243

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