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arXiv · 1509.04018

Spectral characteristics of time resolved magnonic spin Seebeck effect

S. R. Etesami·L. Chotorlishvili·J. Berakdar
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Abstract

Spin Seebeck effect (SSE) holds promise for new spintronic devices with low-energy consumption. The underlying physics, essential for a further progress, is yet to be fully clarified. This study of the time resolved longitudinal SSE in the magnetic insulator yttrium iron garnet (YIG) concludes that a substantial contribution to the spin current stems from small wave-vector subthermal exchange magnons. Our finding is in line with the recent experiment by S. R. Boona and J. P. Heremans, Phys. Rev. B 90, 064421 (2014). Technically, the spin-current dynamics is treated based on the Landau-Lifshitz-Gilbert (LLG) equation also including magnons back-action on thermal bath, while the formation of the time dependent thermal gradient is described self-consistently via the heat equation coupled to the magnetization dynamics

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S. R. Etesami, L. Chotorlishvili, J. Berakdar. 2015-09-14. Spectral characteristics of time resolved magnonic spin Seebeck effect. https://doi.org/10.1063/1.4931701

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