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arXiv · 1808.01192

A thermally driven spin-transfer-torque system far from equilibrium: enhancement of the thermoelectric current via pumping current

Tim Ludwig·Igor S. Burmistrov·Yuval Gefen·Alexander Shnirman
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Abstract

We consider a small itinerant ferromagnet exposed to an external magnetic field and strongly driven by a thermally induced spin current. For this model, we derive the quasi-classical equations of motion for the magnetization where the effects of a dynamical non-equilibrium distribution function are taken into account self-consistently. We obtain the Landau-Lifshitz-Gilbert equation supplemented by a spin-transfer torque term of Slonczewski form. We identify a regime of persistent precessions in which we find an enhancement of the thermoelectric current by the pumping current.

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Tim Ludwig, Igor S. Burmistrov, Yuval Gefen, Alexander Shnirman. 2018-08-03. A thermally driven spin-transfer-torque system far from equilibrium: enhancement of the thermoelectric current via pumping current. https://doi.org/10.1103/physrevb.99.045429

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