Magnons and Phonons Driven out of Equilibrium in a Magnetic Insulator

ORAL

Abstract

We investigate magnons and phonons in a bulk Y$_{3}$Fe$_{5}$O$_{12~}$(YIG) under a large temperature gradient created by laser radiation. YIG is a good playground to study the interaction between phonons and magnons. Because of its absence of itinerant electrons, energy transport is only carried by magnons and phonons. Understanding the coupling between them is a key to the thermally driven spin transport such as Spin Seebeck Effect. We use Brillouin light scattering technique to measure phonon and magnon temperature. We found that they can be driven out of equilibrium under a large temperature gradient. We numerically simulate the phonon and magnon temperatures using two-temperature model. Our results suggest a lower bound of magnon phonon relaxation time in YIG.

*We acknowledge support from DOE, AOR under contract W911NF-14-1-0016 and NSF via grant CBET-1336968.

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Authors

  • Kyongmo An

    • Univ of Texas, Austin
    • Department of Physics, The University of Texas at Austin

  • Kevin Olsson

    • Department of Physics, The University of Texas at Austin

  • Nikita Klimovich

    • Department of Physics, The University of Texas at Austin

  • Sean Sullivan

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Annie Weathers

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Luke Marshall

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Xi Chen

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Jianshi Zhou

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Li Shi

    • Department of Mechanical Engineering, The University of Texas at Austin

  • Xiaoqin Li

    • Department of Physics, The University of Texas at Austin