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DOE OSTI ยท 2568301

Spin-Transfer Torque in Altermagnets with Magnetic Textures

Vakili, Hamed [University of Nebraska, Lincoln, NE (United States)] (ORCID:0000000189714664)ยทSchwartz, Edward [University of Nebraska, Lincoln, NE (United States)]ยทKovalev, Alexey A. [University of Nebraska, Lincoln, NE (United States)] (ORCID:0000000258847154)
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Abstract

We predict the existence of anisotropic spin-transfer torque effect in textured altermagnets. To this end, we generalize the Zhang-Li torque to incorporate the symmetry associated with prototypical ๐‘‘-wave altermagnets and identify the spin-splitter adiabatic and nonadiabatic torques. Applying our results to domain wall dynamics induced by spin-transfer torque, we find that, in certain regimes, the spin-splitter adiabatic torque can induce domain wall precession, significantly slowing down domain wall motion. The response of the domain wall also becomes anisotropic, reflecting the ๐‘‘-wave symmetry of the altermagnet. Furthermore, we observe that the spin-splitter adiabatic torque modifies skyrmion dynamics, inducing anisotropic skyrmion Hall effect. Furthermore, the above phenomena can serve as a hallmark of altermagnetism in textured magnets, distinguishing it from the behavior of ordinary antiferromagnets.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSAltermagnetsDomain wall motionMagnetic textureSpin currentThiele equation

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BibTeXRIS

Vakili, Hamed [University of Nebraska, Lincoln, NE (United States)] (ORCID:0000000189714664), Schwartz, Edward [University of Nebraska, Lincoln, NE (United States)], Kovalev, Alexey A. [University of Nebraska, Lincoln, NE (United States)] (ORCID:0000000258847154). 2025-04-28. Spin-Transfer Torque in Altermagnets with Magnetic Textures. https://doi.org/10.1103/physrevlett.134.176401

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