Thermomagnonic Torques in Insulating Altermagnets

Edward Schwartz; Hamed Vakili; Alexey A. Kovalev

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arXiv · 2512.14660

Thermomagnonic Torques in Insulating Altermagnets

Edward Schwartz·Hamed Vakili·Alexey A. Kovalev

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Abstract

We develop a symmetry-controlled theory of anisotropic thermomagnonic torques in insulating altermagnets. We identify a spin-splitter magnonic torque linked to thermally generated, sublattice-odd spin currents and an anisotropic entropic torque dictated by crystal symmetry. These torques produce anisotropic magnetic-texture responses to temperature gradients. In particular, thermally generated spin currents induce domain-wall precession, which reduces domain-wall velocities for selected gradient directions. We also predict an anisotropic skyrmion Hall response, with symmetry-selected directions enabling fast skyrmion motion with strongly suppressed transverse deflection. Our results reveal experimentally testable symmetry fingerprints of insulating altermagnets and extend more broadly to anisotropic magnets with exchange-driven magnon spin splitting.

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Edward Schwartz, Hamed Vakili, Alexey A. Kovalev. 2025-12-16. Thermomagnonic Torques in Insulating Altermagnets. https://arxiv.org/abs/2512.14660

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