Thermally induced spin torque and domain wall motion in superconductor/antiferromagnetic insulator bilayers

G. A. Bobkov; I. V. Bobkova; A. M. Bobkov; Akashdeep Kamra

doi:10.1103/physrevb.103.094506

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arXiv · 2012.07405

Thermally induced spin torque and domain wall motion in superconductor/antiferromagnetic insulator bilayers

G. A. Bobkov·I. V. Bobkova·A. M. Bobkov·Akashdeep Kamra

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Abstract

We theoretically investigate domain wall motion in an antiferromagnetic insulator layer caused by thermally generated spin currents in an adjacent spin-split superconductor layer. An uncompensated antiferromagnet interface enables the two crucial ingredients underlying the mechanism - spin splitting in the superconductor and absorption of spin currents by the antiferromagnet. Treating the superconductor using the quasiclassical theory and the antiferromagnet via Landau-Lifshitz-Gilbert description, we find domain wall propagation along the thermal gradient with relatively large velocities $\sim 100$ m/s. Our proposal exploits the giant thermal response of spin-split superconductors in achieving large spin torques towards driving domain wall and other spin textures in antiferromagnets.

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G. A. Bobkov, I. V. Bobkova, A. M. Bobkov, Akashdeep Kamra. 2020-12-14. Thermally induced spin torque and domain wall motion in superconductor/antiferromagnetic insulator bilayers. https://doi.org/10.1103/physrevb.103.094506

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