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Single Shot Ultrafast All Optical Magnetization Switching of Ferromagnetic Co/Pt Multilayers

Magneto-optical images of a GdFeCo/[Co/Pt] stack, that illustrate the possibility of switching the magnetization in both layers, via single linearly polarized laser shots.

Scientific Achievement
Demonstrated magnetization switching of ferromagnetic films, within 7 picoseconds, via single laser shots.

Significance and Impact
Harnessing the strong exchange coupling between a ferri- and a ferro-magnetic film for ultrafast all-optical switching of the ferromagnet expands greatly the suitable class of materials for ultrafast spintronic applications.

Research Details

  • Ferromagnetic Co/Pt multilayers are grown on top of ferrimagnetic GdFeCo films.
  • Single femtosecond laser pulses (of any polarization) are known to induce the reversal of GdFeCo magnetization, but here both layers switch after a laser shot due to the exchange coupling with the Co/Pt.
  • Depth-sensitive and time-resolved magneto-optical measurements determined the fast dynamics of each magnetic layer.

J. Gorchon, Ch.-H. Lambert, Y. Yang, A. Pattabi, R.B. Wilson, S. Salahuddin, J. Bokor, Applied Physics Letters 111, 042401 (2017) DOI: 10.1063/1.4994802