Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 23: Magnetization / Demagnetization Dynamics II
MA 23.1: Hauptvortrag
Mittwoch, 28. März 2012, 09:30–10:00, H 1012
Uncovering the Ultrafast Angular Momentum Transfer on the Nanoscale in GdFeCo — •A. Scherz1, C. Graves1,2, A.H. Reid1, B. Wu1,2, T. Wang1,2, S. de Jong2, K. Vahaplar3, I. Radu3, M. Messerschmidt4, R. Coffee4, M. Bionta4, R. Hartmann5, N. Kimmel5, S. Epp5, A. Tsukamoto6, J. Turner4, W.F. Schlotter4, Y. Acremann7, A. Kimel3, A. Kirilyuk3, J. Stöhr1,4, T. Rasing3, and H. Dürr1 — 1Stanford Inst. for Material and Energy Science, California — 2Stanford University, California — 3Radboud University Nijmegen, Netherlands — 4LCLS, SLAC Nat. Acc. Lab., California — 5ASG-MPG, CFEL Hamburg, Germany — 6Nihon University, Japan — 7ETH Zürich, Switzerland
The ultrafast control of electron spins is of both fundamental scientific and technological interest. Recent experiments have shown that femtosecond laser excitation can act as a stimulus to switch the direction of the magnetization in ferrimagnetic GdFeCo, called all-optical switching. However, how angular momentum is transferred to result in a switched state remains unknown. To further understand this mechanism, we used the fs x-ray pulses at the x-ray free electron laser facility, LCLS, to study the all-optical magnetization switching of GdFeCo triggered by fs laser excitation using time-, element- and spatially-resolved x-ray resonant magnetic scattering. We present here the first-ever measurement of the fs magnetic response in GdFeCo with spatial resolution down to 10nm. Our results reveal drastically different behaviors on the nanoscale as compared to the bulk and provide insight into the angular momentum transfer channels.