Ultrafast Optical Demagnetization manipulates Nanoscale Spin Structure in Domain Walls
During ultrafast demagnetization of a magnetically ordered solid, angular momentum has to be transferred between the spins, electrons, and phonons in the system on femto- and picosecond timescales. Although the intrinsic spin-transfer mechanisms are intensely debated, additional extrinsic mechanisms arising due to nanoscale heterogeneity have only recently entered the discussion. Here we use femtosecond X-ray pulses from a free-electron laser to study thin film samples with magnetic domain patterns. We observe an infrared-pump-induced change of the spin structure within the domain walls on the sub-picosecond timescale. This domain-topography-dependent contribution connects the intrinsic dem…
Ultrafast Dynamics of Magnetic Domain Structures Probed by Coherent Free-Electron Laser Light
Synchrotron radiation news 26(6), 27 - 32 (2013). doi:10.1080/08940886.2013.850384