Ultrafast Demagnetization Measurements using Extreme Ultraviolet Light: Comparison of Electronic and Magnetic Contributions

ORAL

Abstract

Ultrashort pulses from high-harmonic generation provide new capabilities for uncovering coupled charge, spin, and phonon dynamics in magnetic materials by combining elemental selectivity with ultrafast time resolution in a tabletop source. In this talk, we address an important question in magneto-optics that has implications for understanding femtosecond magnetism: is the signal from the transverse magneto-optical Kerr effect at the M-shell absorption edges of a magnetic material purely magnetic or perturbed by non-magnetic optical artifacts? We conclusively show that high harmonics sensitively probe the magnetic state, with negligible contributions from electronic effects because of hot-electron dynamics. Finally, our measurements are in excellent agreement with conventional visible-wavelength magneto-optics probes and illustrate the power of high harmonics for probing the dynamics in magnetic materials.

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Authors

  • Chan La-o-vorakiat

    • JILA/University of Colorado

  • Emrah Turgut

    • JILA/University of Colorado

  • Carson A. Teale

    • JILA/University of Colorado

  • Henry C. Kapteyn

    • JILA/University of Colorado

  • Margaret M. Murnane

    • JILA/University of Colorado

  • Denis Lvovsky

    • Peter Gr\"unberg Institute, J\"ulich, Germany

  • Roman Adam

    • Peter Gr\"unberg Institute, J\"ulich, Germany

  • Patrik Grychtol

    • Peter Gr\"unberg Institute, J\"ulich, Germany

  • Claus M. Schneider

    • Peter Gr\"unberg Institute, J\"ulich, Germany

  • Stefan Mathias

    • University of Kaiserslautern and Research Center OPTIMAS

  • Martin Aeschlimann

    • University of Kaiserslautern and Research Center OPTIMAS

  • Justin M. Shaw

    • National Institute of Standards and Technology

  • Hans Nembach

    • National Institute of Standards and Technology

  • Thomas J. Silva

    • National Institute of Standards and Technology