title: Large Spin-Wave Bullet in a Ferrimagnetic Insulator Driven by the Spin Hall Effect.
abstract: Because of its transverse nature, spin Hall effects (SHE) provide the possibility to excite and detect spin currents and magnetization dynamics even in magnetic insulators. Magnetic insulators are outstanding materials for the investigation of nonlinear phenomena and for novel low power spintronics applications because of their extremely low Gilbert damping. Here, we report on the direct imaging of electrically driven spin-torque ferromagnetic resonance (ST-FMR) in the ferrimagnetic insulator Y_{3}Fe_{5}O_{12} based on the excitation and detection by SHEs. The driven spin dynamics in Y_{3}Fe_{5}O_{12} is directly imaged by spatially resolved microfocused Brillouin light scattering spectroscopy. Previously, ST-FMR experiments assumed a uniform precession across the sample, which is not valid in our measurements. A strong spin-wave localization in the center of the sample is observed indicating the formation of a nonlinear, self-localized spin-wave "bullet".
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Jungfleisch
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.|Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: J
authors.initials: J
authors.lastname: Sklenar
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: J
authors.initials: J
authors.lastname: Ding
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: W
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA.
authors.forename: H
authors.initials: H
authors.lastname: Chang
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: F Y
authors.initials: FY
authors.lastname: Fradin
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Pearson
authors.affiliation: Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Ketterson
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: V
authors.initials: V
authors.lastname: Novosad
authors.affiliation: Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA.
authors.forename: M
authors.initials: M
authors.lastname: Wu
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: A
authors.initials: A
authors.lastname: Hoffmann