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arXiv · 1607.03263

Thermal spin dynamics of yttrium iron garnet

Joseph Barker·Gerrit E. W. Bauer
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Abstract

Yttrium Iron Garnet is the prototypical material used to study pure spin currents. It is a complex material with 20 magnetic atoms in the unit cell. Almost all theories and experimental analysis approximates this complicated material to a simple ferromagnet with a single spin wave mode. We use the method of atomistic spin dynamics to study the temperature evolution of the full 20 mode exchange spin wave spectrum. Our results show a strong frequency dependence of the modes in quantitative agreement with neutron scattering experiments. We find this causes in a reduction in the net spin pumping due to the thermal occupation of optical modes with the opposite chirality to the FMR mode.

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Joseph Barker, Gerrit E. W. Bauer. 2016-07-12. Thermal spin dynamics of yttrium iron garnet. https://doi.org/10.1103/physrevlett.117.217201

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