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arXiv · 2011.07541

Cryogenic spin Seebeck effect

Mehrdad Elyasi·Gerrit E. W. Bauer
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Abstract

We present a theory of the non-linearities of the spin Seebeck effect (SSE) in a ferromagnetic nanowire at cryogenic temperatures. We adopt a microscopic quantum noise model based on a collection of two-level systems. At certain positions of Pt detectors to the wire, the transverse SSE changes sign as a function of temperature and/or temperature gradient. On the other hand, the longitudinal SSE does not show significant non-linearities even far outside the regime of validity of linear response theory.

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Mehrdad Elyasi, Gerrit E. W. Bauer. 2020-11-15. Cryogenic spin Seebeck effect. https://doi.org/10.1103/physrevb.103.054436

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