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arXiv · 1404.2360

Current-induced spin torque resonance of magnetic insulators

Takahiro Chiba·Gerrit E. W. Bauer·Saburo Takahashi
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Abstract

We formulate a theory of the AC spin Hall magnetoresistance (SMR) in a bilayer system consisting of a magnetic insulator such as yttrium iron garnet (YIG) and a heavy metal such as platinum (Pt). We derive expressions for the DC voltage generation based on the drift-diffusion spin model and quantum mechanical boundary condition at the interface that reveal a spin torque ferromagnetic resonance (ST-FMR). We predict that ST-FMR experiments will reveal valuable information on the current-induced magnetization dynamics of magnetic insulators and AC spin Hall effect.

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Takahiro Chiba, Gerrit E. W. Bauer, Saburo Takahashi. 2014-08-20. Current-induced spin torque resonance of magnetic insulators. https://doi.org/10.1103/physrevapplied.2.034003

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