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arXiv · 1607.02312

Magnon Polarons in the Spin Seebeck Effect

Takashi Kikkawa·Ka Shen·Benedetta Flebus·Rembert A. Duine·Ken-ichi Uchida·Zhiyong Qiu·Gerrit E. W. Bauer·Eiji Saitoh
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Abstract

Sharp structures in magnetic field-dependent spin Seebeck effect (SSE) voltages of Pt/Y$_{3}$Fe$_{5}$O$_{12}$ (YIG) at low temperatures are attributed to the magnon-phonon interaction. Experimental results are well reproduced by a Boltzmann theory that includes the magnetoelastic coupling (MEC). The SSE anomalies coincide with magnetic fields tuned to the threshold of magnon-polaron formation. The effect gives insight into the relative quality of the lattice and magnetization dynamics.

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Takashi Kikkawa, Ka Shen, Benedetta Flebus, Rembert A. Duine, Ken-ichi Uchida, Zhiyong Qiu, Gerrit E. W. Bauer, Eiji Saitoh. 2016-10-27. Magnon Polarons in the Spin Seebeck Effect. https://doi.org/10.1103/physrevlett.117.207203

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