von Korff Schmising, C.; Pfau, B.; Schneider, M.; Günther, C.M.; Giovannella, M.; Perron, J.; Vodungbo, B.; Müller, L.; Capotondi, F.; Pedersoli, E.; Mahne, N.; Lüning, J.; Eisebitt, S.: Imaging Ultrafast Demagnetization Dynamics after a Spatially Localized Optical Excitation. Physical Review Letters 112 (2014), p. 217203
10.1103/PhysRevLett.112.217203
Open Access Version (externer Anbieter)
Abstract:
Ultrashort, coherent x-ray pulses of a free-electron laser are used to holographically image the magnetization dynamics within a magnetic domain pattern after creation of a localized excitation via an optical standing wave. We observe a spatially confined reduction of the magnetization within a couple of hundred femtoseconds followed by its slower recovery. Additionally, the experimental results show evidence of a spatial evolution of magnetization, which we attribute to ultrafast transport of nonequilibrium spin-polarized electrons for early times and to a fluence-dependent remagnetization rate for later times.