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Magnonics pp 177-187 | Cite as

Nano-Contact Spin-Torque Oscillators as Magnonic Building Blocks

  • Stefano Bonetti
  • Johan Åkerman
Chapter
Part of the Topics in Applied Physics book series (TAP, volume 125)

Abstract

We describe the possibility of using nano-contact spin-torque oscillators (NC-STOs) as fundamental magnonic building blocks. NC-STOs can act as spin wave generators, manipulators, and detectors, and can hence realize all the fundamental functions necessary for fully integrated magnonic devices, which can be fabricated using available CMOS compatible large-scale spin-torque device production processes. We show in particular how a 200 nm sized nano-contact located on an out-of-plane magnetized permalloy “free” magnetic layer can generate spin waves at f≈15 GHz that propagate up to 4 μm away from the nano-contact with wavelength λ=200–300 nm, decay length λ r ≈2 μm and group velocities v g ≈3 μm/ns. We propose that the same type of NC-STOs can be used as spin wave manipulators, via control of the local Gilbert damping, and as spin wave detector using the spin torque diode effect.

Keywords

Spin Wave Magnetic Layer Decay Length Free Layer Perpendicular Magnetic Anisotropy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

Support from the Swedish Foundation for Strategic Research (SSF), the Swedish Research Council (VR) and the Knut and Alice Wallenberg Foundation is gratefully acknowledged. Stefano Bonetti is a Postdoctoral Fellow supported by a grant from the Swedish Research Council (VR) and the Knut and Alice Wallenberg Foundation. Johan Åkerman is a Royal Swedish Academy of Sciences Research Fellow supported by a grant from the Knut and Alice Wallenberg Foundation. We thank M. Madami, G. Consolo, S. Tacchi, G. Carlotti, G. Gubbiotti, F.B. Mancoff, V. Tiberkevich, and A. Slavin for useful discussions.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.School of Information and Communication Technology, Materials PhysicsKTH – Royal Institute of TechnologyKista-StockholmSweden
  2. 2.Department of PhysicsUniversity of GothenburgGothenburgSweden
  3. 3.Stanford Institute for Materials and Energy Science (SIMES)Stanford UniversityStanfordUSA

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