title: Direct imaging of thermally driven domain wall motion in magnetic insulators.
abstract: Thermally induced domain wall motion in a magnetic insulator was observed using spatiotemporally resolved polar magneto-optical Kerr effect microscopy. The following results were found: (i) the domain wall moves towards hot regime; (ii) a threshold temperature gradient (5  K/mm), i.e., a minimal temperature gradient required to induce domain wall motion; (iii) a finite domain wall velocity outside of the region with a temperature gradient, slowly decreasing as a function of distance, which is interpreted to result from the penetration of a magnonic current into the constant temperature region; and (iv) a linear dependence of the average domain wall velocity on temperature gradient, beyond a threshold thermal bias. Our observations can be qualitatively explained using a magnonic spin transfer torque mechanism, which suggests the utility of magnonic spin transfer torque for controlling magnetization dynamics.
authors.affiliation: Department of Electrical Engineering, Device Research Laboratory, University of California, Los Angeles, California 90095, USA.
authors.forename: Wanjun
authors.initials: W
authors.lastname: Jiang
authors.forename: Pramey
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authors.lastname: Upadhyaya
authors.forename: Yabin
authors.initials: Y
authors.lastname: Fan
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Minsheng
authors.initials: M
authors.lastname: Wang
authors.forename: Li-Te
authors.initials: LT
authors.lastname: Chang
authors.forename: Murong
authors.initials: M
authors.lastname: Lang
authors.forename: Kin L
authors.initials: KL
authors.lastname: Wong
authors.forename: Mark
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authors.lastname: Lewis
authors.forename: Yen-Ting
authors.initials: YT
authors.lastname: Lin
authors.forename: Jianshi
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authors.lastname: Tang
authors.forename: Sergiy
authors.initials: S
authors.lastname: Cherepov
authors.forename: Xuezhi
authors.initials: X
authors.lastname: Zhou
authors.forename: Yaroslav
authors.initials: Y
authors.lastname: Tserkovnyak
authors.forename: Robert N
authors.initials: RN
authors.lastname: Schwartz
authors.forename: Kang L
authors.initials: KL
authors.lastname: Wang