Thermomagnonic torques in insulating altermagnets
Phys. Rev. B 114, 274419 – Published 12 November, 2026
DOI: https://doi.org/10.1103/918g-3q7f
Abstract
We develop a symmetry-controlled theory of anisotropic thermomagnonic torques in insulating altermagnets. Starting from the stochastic Landau-Lifshitz-Gilbert equations, we identify a spin-splitter magnonic torque associated with 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.
