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

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Author(s): Thomas J. Silva; Justin M. Shaw; Hans T. Nembach; Margaret M. Murnane; Henry C. Kapteyn; Chan La-O-Vorakiat; Stefan Mathias; Emrah Turgut; Teale A. Carson; Martin Aeschlimann; Claus M. Schneider;
Title: Ultrafast Demagnetization Measurements using Extreme Ultraviolet Light: Comparison of Electronic and Magnetic Contributions
Published: January 23, 2012
Abstract: Ultrashort pulses of extreme ultraviolet light from high-harmonic generation are a new tool for probing coupled charge, spin, and phonon dynamics with element specificity, attosecond pump-probe synchronization, and time resolution of a few-femtoseconds in a tabletop apparatus. In this paper, we address an important question in magneto-optics that has implications for understanding magnetism on the fastest time scales: Is the signal from the transverse magneto-optical Kerr effect at the M2,3 edges of a magnetic material purely magnetic or is it perturbed by nonmagnetic artifacts? Our measurements demonstrate conclusively that transverse magneto-optical Kerr measurements at the M2,3 edges sensitively probe the magnetic state, with almost negligible contributions from the transient variation of the refractive index by the nonequilibrium hot-electron distribution. In addition, we compare pump-probe demagnetization dynamics measured by both high harmonics and conventional visible-wavelength magneto-optics and find that the measured demagnetization times are in agreement.
Citation: Physical Review
Volume: 2
Issue: 011005
Pages: pp. 011005-1 - 011005-7
Keywords: ultrafast demagnetization;high harmonic generation;transverse magneto-optic Kerr effect;magnetization dynamics;extreme ultraviolet
Research Areas: Condensed Matter Physics, Magnetics, Optical Physics
PDF version: PDF Document Click here to retrieve PDF version of paper (903KB)