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Spin Transfer Torque Driven Magnetodynamical Solitons

  • Johan Åkerman
Chapter
Part of the Springer Series in Solid-State Sciences book series (SSSOL, volume 192)

Abstract

The recent progress in generating high spin current densities in magnetic nanostructures has made it possible to excite unprecedented magnon densities from which a range of novel magnetodynamical solitons, such as spin wave bullets, magnetic droplets, and dynamical skyrmions can nucleate. In this chapter, these magnetodynamical solitons, and the devices where they can be created and observed - so-called spin torque and spin Hall nano-oscillators are discussed in detail. The solitons form under conditions of magnon-magnon attraction, which arises when the magnetodynamics exhibits negative non-linearity, and the resulting particle-like objects exhibit a rich dynamics including Brownian motion, drift instabilities, perimeter eigenmode excitations, and merging. While originally only observed indirectly using microwave spectroscopy, these solitons can now also be observed directly using scanning transmission x-ray microscopy.

Notes

Acknowledgements

Discussions with M. Ahlberg, A. A. Awad, S. Chung, R. K. Dumas, M. Dvornik, A. Houshang, S. M. Mohseni, R. Khymyn, and Y. Zhou are gratefully acknowledged. Work funded by The Swedish Research Council, The Knut and Alice Wallenberg Foundation, and the Gäran Gustafsson Foundation.

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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of GothenburgGothenburgSweden
  2. 2.Materials and NanophysicsKTH Royal Institute of TechnologyKistaSweden

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