Regensburg 2013 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MA: Fachverband Magnetismus
MA 33: Magnetization Dynamics I of 3
MA 33.1: Talk
Thursday, March 14, 2013, 09:30–09:45, H22
Ultrafast transiently inversed magnetization in TbCo alloys — •Sabine Alebrand1, Ute Bierbrauer1, Michel Hehn2, Matthias Gottwald2,3, Oliver Schmitt1, Daniel Steil1, Eric E. Fullerton3, Stéphane Mangin2, Mirko Cinchetti1, and Martin Aeschlimann1 — 1Dep. of Physics and Research Center OPTIMAS, University of Kaiserslautern, Germany — 2IJL, Université de Lorraine, Nancy, France — 3University of California, San Diego, USA
Since the discovery of all-optical magnetization switching in 2007 [1], the rare earth (RE) -transition metal (TM) alloy GdFeCo gained special attention. In 2011 Radu et al. [2] performed an XMCD experiment on GdFeCo, which allows to detect the magnetization dynamics of both the Gd- and FeCo-sublattice seperately. They found that the two sublattices not only demagnetize after laser exciation but they can even transiently be switched on a subpicosecond timescale.
We focus on the RE-TM alloy TbCo which combines all-optical switching with high perpendicular anisotropy [3]. We performed time-resolved magneto-optical Kerr measurements, investigating the fluence and composition dependent ultrafast demagnetization behavior. We find that for equal excitation conditions the demagnetization strength of the Co sublattice strongly depends on the Tb concentration. Moreover for Tb32Co68 we observe a transient magnetization switching of the Co sublattice on a timescale similar the one in GdFeCo. The magnetization switched state can last for several picoseconds.
[1] Stanciu et al. PRL 99, 047601 (2007) [2] Radu et al. Nature 472, 205-208 (2011) [3] Alebrand et al. APL 101, 162408 (2012)