Experiments of time-resolved x-ray magnetic circular dichroism (Tr-XMCD) and resonant x-ray scattering at a beamline BL07LSU in SPring-8 with a time-resolution of under 50 ps are presented. A micro-channel plate is utilized for the Tr-XMCD measurements at nearly normal incidence both in the partial electron and total fluorescence yield (PEY and TFY) modes at the L2,3 absorption edges of the 3d transition-metals in the soft x-ray region. The ultrafast photo-induced demagnetization within 50 ps is observed on the dynamics of a magnetic material of FePt thin film, having a distinct threshold of the photon density. The spectrum in the PEY mode is less-distorted both at the L2,3 edges compared with that in the TFY mode and has the potential to apply the sum rule analysis for XMCD spectra in pump-probed experiments.
@article{arxiv.1701.03156,
title = {Capturing ultrafast magnetic dynamics by time-resolved soft x-ray magnetic circular dichroism},
author = {Kou Takubo and Kohei Yamamoto and Yasuyuki Hirata and Yuichi Yokoyama and Yuya Kubota and Shingo Yamamoto and Susumu Yamamoto and Iwao Matsuda and Shik Shin and Takeshi Seki and Koki Takanashi and Hiroki Wadati},
journal= {arXiv preprint arXiv:1701.03156},
year = {2017}
}