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

Published

January 23, 2012

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

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 M_2,3 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 M_2,3 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

Pub Type

Journals

Download Paper

Local Download

Keywords

ultrafast demagnetization, high harmonic generation, transverse magneto-optic Kerr effect, magnetization dynamics, extreme ultraviolet

Citation

Silva, T. , Shaw, J. , Nembach, H. , Murnane, M. , Kapteyn, H. , La-O-Vorakiat, C. , Mathias, S. , Turgut, E. , Carson, T. , Aeschlimann, M. and Schneider, C. (2012), Ultrafast Demagnetization Measurements using Extreme Ultraviolet Light: Comparison of Electronic and Magnetic Contributions, Physical Review, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=910037 (Accessed October 7, 2025)