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Magnetothermopower and magnon-assisted transport in ferromagnetic tunnel junctions

Edward McCann·Vladimir I. Fal'ko
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Abstract

We present a model of the thermopower in a mesoscopic tunnel junction between two ferromagnetic metals based upon magnon-assisted tunneling processes. In our model, the thermopower is generated in the course of thermal equilibration between two baths of magnons, mediated by electrons. We predict a particularly large thermopower effect in the case of a junction between two half-metallic ferromagnets with antiparallel polarizations, $S_{AP} \sim - (k_B/e)$, in contrast to $S_{P} \approx 0$ for a parallel configuration.

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Edward McCann, Vladimir I. Fal'ko. 2002-02-26. Magnetothermopower and magnon-assisted transport in ferromagnetic tunnel junctions. https://doi.org/10.1063/1.1519730

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