Applied Sciences (Oct 2020)

Element-Specific Magnetization Dynamics of Complex Magnetic Systems Probed by Ultrafast Magneto-Optical Spectroscopy

  • Clemens von Korff Schmising,
  • Felix Willems,
  • Sangeeta Sharma,
  • Kelvin Yao,
  • Martin Borchert,
  • Martin Hennecke,
  • Daniel Schick,
  • Ilie Radu,
  • Christian Strüber,
  • Dieter W. Engel,
  • Vishal Shokeen,
  • Jens Buck,
  • Kai Bagschik,
  • Jens Viefhaus,
  • Gregor Hartmann,
  • Bastian Manschwetus,
  • Soeren Grunewald,
  • Stefan Düsterer,
  • Emmanuelle Jal,
  • Boris Vodungbo,
  • Jan Lüning,
  • Stefan Eisebitt

DOI
https://doi.org/10.3390/app10217580
Journal volume & issue
Vol. 10, no. 21
p. 7580

Abstract

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The vision to manipulate and control magnetism with light is driven on the one hand by fundamental questions of direct and indirect photon-spin interactions, and on the other hand by the necessity to cope with ever growing data volumes, requiring radically new approaches on how to write, read and process information. Here, we present two complementary experimental geometries to access the element-specific magnetization dynamics of complex magnetic systems via ultrafast magneto-optical spectroscopy in the extreme ultraviolet spectral range. First, we employ linearly polarized radiation of a free electron laser facility to demonstrate decoupled dynamics of the two sublattices of an FeGd alloy, a prerequisite for all-optical magnetization switching. Second, we use circularly polarized radiation generated in a laboratory-based high harmonic generation setup to show optical inter-site spin transfer in a CoPt alloy, a mechanism which only very recently has been predicted to mediate ultrafast metamagnetic phase transitions.

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