Magnon spin transport in magnetic insulators

Ludo Johannes Cornelissen

Research output: ThesisThesis fully internal (DIV)

1898 Downloads (Pure)

Abstract

Magnons or spin waves occur in magnetic materials. A spin wave is a vibration in the magnetic property of the material: The magnetic north- and southpole of the atoms in a magnet are not fixed in place, but can vibrate about their equilibrium position. Spin waves are known to exist for more than half a century already, but in this thesis we show that they can be excited and detected using a relatively simple technique. Using nanofabrication, we make a very small spin wave injector and spin wave detector on the surface of a magnet: By passing a small electrical current through the injector, spin waves are excited in the magnet. When these waves arrive at the detector, they generate a voltage, which we measure.

Using this technique to send and receive spin waves we were able to answer various open questions regarding their behaviour: How do they propagate? Do they travel in straight lines or bounce around? How do they respond to a strong magnetic field? And is it possible not just to generate and detect them, but also manipulate them as they propagate in the magnet?

Spin waves may find applications in computer technology, since theoretically they can perform certain calculations very efficiently. In addition, they are well suited for the integration of memory within logic circuits, which would increase the efficiency of the processor. Plenty of further research is required before this can be realized, but this thesis is one of the first steps in that direction.
Translated title of the contributionSpin transport door magnonen in magnetische isolatoren
Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • University of Groningen
Supervisors/Advisors
  • van Wees, Bart, Supervisor
  • Kooi, Bart, Supervisor
Award date8-Jun-2018
Place of Publication[Groningen]
Publisher
Print ISBNs978-94-034-0505-6
Electronic ISBNs978-94-034-0504-9
Publication statusPublished - 2018

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