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arXiv · 1409.8513

Spin Hall noise

Akashdeep Kamra·Friedrich P. Witek·Sibylle Meyer·Hans Huebl·Stephan Geprägs·Rudolf Gross·Gerrit E. W. Bauer·Sebastian T. B. Goennenwein
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Abstract

We measure the low-frequency thermal fluctuations of pure spin current in a Platinum film deposited on yttrium iron garnet via the inverse spin Hall effect (ISHE)-mediated voltage noise as a function of the angle $α$ between the magnetization and the transport direction. The results are consistent with the fluctuation dissipation theorem in terms of the recently discovered spin Hall magnetoresistance (SMR). We present a microscopic description of the $α$ dependence of the voltage noise in terms of spin current fluctuations and ISHE.

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Akashdeep Kamra, Friedrich P. Witek, Sibylle Meyer, Hans Huebl, Stephan Geprägs, Rudolf Gross, Gerrit E. W. Bauer, Sebastian T. B. Goennenwein. 2014-12-17. Spin Hall noise. https://doi.org/10.1103/physrevb.90.214419

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