title: Magnons and Phonons Optically Driven out of Local Equilibrium in a Magnetic Insulator.
abstract: The coupling and possible nonequilibrium between magnons and other energy carriers have been used to explain several recently discovered thermally driven spin transport and energy conversion phenomena. Here, we report experiments in which local nonequilibrium between magnons and phonons in a single crystalline bulk magnetic insulator, Y_{3}Fe_{5}O_{12}, has been created optically within a focused laser spot and probed directly via micro-Brillouin light scattering. Through analyzing the deviation in the magnon number density from the local equilibrium value, we obtain the diffusion length of thermal magnons. By explicitly establishing and observing local nonequilibrium between magnons and phonons, our studies represent an important step toward a quantitative understanding of various spin-heat coupling phenomena.
authors.affiliation: Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Kyongmo
authors.initials: K
authors.lastname: An
authors.affiliation: Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Kevin S
authors.initials: KS
authors.lastname: Olsson
authors.affiliation: Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Annie
authors.initials: A
authors.lastname: Weathers
authors.affiliation: Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Sullivan
authors.affiliation: Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.affiliation: Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.affiliation: Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Luke G
authors.initials: LG
authors.lastname: Marshall
authors.affiliation: Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Nikita
authors.initials: N
authors.lastname: Klimovich
authors.affiliation: Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.|Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Jianshi
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.|Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Shi
authors.affiliation: Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, USA.|Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Li