Nanoscale transient gratings of magnetization induced by extreme ultraviolet light

ORAL

Abstract

We describe a methodology for generating and probing periodic nanoscale patterns of magnetization using femtosecond extreme ultraviolet (EUV) pulses from a free electron laser. Two EUV pulses crossed at the sample surface excite a magnetization grating with a period in the tens of nanometers range; the dynamics of this grating are monitored via diffraction of a time-delayed EUV pulse tuned to the M-edge of a transition metal element. The magnetization grating emerges on a subpicosecond time scale as the sample is demagnetized at the maxima of the EUV pump intensity and decay on the time scale of tens of picoseconds. Following the initial report [1], we improved the setup by adding a polarizing mirror analyzer that enables the separation of magnetic and non-magnetic responses of the sample.  We will describe experiments conducted on Co-Ni and Co-Pt multilayers as well as on a CoGd alloy with perpendicular magnetic anisotropy and discuss the dependence of the observed dynamics on the grating period and the pump fluence. We will propose several avenues for studying ultrafast magnetic dynamics on the nanoscale using the transient magnetic gratings approach.

 

[1] D. Ksenzov et al., Nano Lett. 21, 2905 (2021).

*A.A.M., J. D. and K.A.N.acknowledge support from the U.S. Department of Energy under Award DE-SC0019126; V.U., M.P. and S.B. acknowledge support from the European Research Council, Starting Grant 715452 MAGNETIC-SPEED-LIMIT; S.U. acknowledges the NSF ECCS award 1804198.

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Presenters

  • Alexei A Maznev

    • Massachusetts Institute of Technology MI
    • Massachusetts Institute of Technology

Authors

  • Alexei A Maznev

    • Massachusetts Institute of Technology MI
    • Massachusetts Institute of Technology

  • Filippo Bencivenga

    • Elettra Sincrotrone Trieste

  • Stefano Bonetti

    • Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden and Ca Foscari University of Venice, 30123 Venice, Italy
    • Stockholm University, Ca' Foscari University of Venice
    • Stockholm Univ

  • Flavio Capotondi

    • Elettra Sinchrotrone Trieste

  • Jude Deschamps

    • Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
    • MIT

  • Laura Foglia

    • Elettra Sinchrotrone Trieste

  • Christian Gutt

    • University of Siegen

  • Dmitriy Ksenzov

    • University of Siegen

  • Claudio Masciovecchio

    • Elettra Sinchrotrone Trieste

  • Alessadra Milloch

    • Elettra Sinchrotrone Trieste

  • Riccardo Mincigrucci

    • Elettra Sinchrotrone Trieste

  • Keith A Nelson

    • Massachusetts Institute of Technology MIT
    • MIT
    • Massachusetts Institute of Technology
    • Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA

  • Jacopo Stefano Pelli Cresi

    • Elettra Sinchrotrone Trieste

  • Thomas Pezeril

    • MIT
    • Institut de Physique de Rennes, UMR CNRS 6251, Université Rennes 1, 35042 Rennes, France
    • Univ Rennes

  • Björn Wehinger

    • Elettra Sinchrotrone Trieste

  • Vivek Unikandanunni

    • Stockholm University
    • Univ Stockholm

  • Sergei Urazhdin

    • Emory University

  • Matteo Pancaldi

    • Stockholm U