Direct observation and imaging of a spin-wave soliton with p-like symmetry

S Bonetti; R Kukreja; Z Chen; F Macià; J M Hernàndez; A Eklund; D Backes; J Frisch; J Katine; G Malm; S Urazhdin; A D Kent; J Stöhr; H Ohldag; H A Dürr

doi:10.1038/ncomms9889

Direct observation and imaging of a spin-wave soliton with p-like symmetry

Nat Commun. 2015 Nov 16:6:8889. doi: 10.1038/ncomms9889.

Authors

S Bonetti^{1

2}, R Kukreja^{2

3}, Z Chen^{1

2}, F Macià⁴, J M Hernàndez⁴, A Eklund⁵, D Backes⁶, J Frisch⁷, J Katine⁸, G Malm⁵, S Urazhdin⁹, A D Kent⁶, J Stöhr², H Ohldag¹⁰, H A Dürr²

Affiliations

¹ Department of Physics, Stanford University, Stanford, California 94305, USA.
² Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
³ Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
⁴ Grup de Magnetisme, Departament de Física Fonamental, Universitat de Barcelona, Barcelon 08028, Spain.
⁵ Integrated Devices and Circuits, School of Information and Communication Technology, KTH Royal Institute of Technology, Kista 16440, Sweden.
⁶ Department of Physics, New York University, 4 Washington Place, New York, New York 10003, USA.
⁷ Advanced Instrumentation for Research Division, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
⁸ HGST, a Western Digital Company, 3403 Yerba Buena Road, San Jose, California 95135, USA.
⁹ Department of Physics, Emory University, 201 Dowman Drive, Atlanta, Georgia 30322, USA.
¹⁰ Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.

Abstract

Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no direct experimental observation exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50 ps temporal resolution and 35 nm spatial resolution, we are able to create a real-space spin-wave movie and observe the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.