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arXiv · 2104.06518

Theory of spin-Hall magnetoresistance in the AC (terahertz) regime

David A. Reiss·Tobias Kampfrath·Piet W. Brouwer
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Abstract

In bilayers consisting of a normal metal (N) with spin-orbit coupling and a ferromagnet (F), the combination of the spin-Hall effect, the spin-transfer torque, and the inverse spin-Hall effect gives a small correction to the in-plane conductivity of N, which is referred to as spin-Hall magnetoresistance (SMR). We here present a theory of the SMR and the associated off-diagonal conductivity corrections for frequencies up to the terahertz regime. We show that the SMR signal has pronounced singularities at the spin-wave frequencies of F, which identifies it as a potential tool for all-electric spectroscopy of magnon modes. A systematic change of the magnitude of the SMR at lower frequencies is associated with the onset of a longitudinal magnonic contribution to spin transport across the F-N interface.

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David A. Reiss, Tobias Kampfrath, Piet W. Brouwer. 2021-04-13. Theory of spin-Hall magnetoresistance in the AC (terahertz) regime. https://doi.org/10.1103/physrevb.104.024415

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