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arXiv · 1701.03156

Capturing ultrafast magnetic dynamics by time-resolved soft x-ray magnetic circular dichroism

Kou Takubo·Kohei Yamamoto·Yasuyuki Hirata·Yuichi Yokoyama·Yuya Kubota·Shingo Yamamoto·Susumu Yamamoto·Iwao Matsuda·Shik Shin·Takeshi Seki·Koki Takanashi·Hiroki Wadati
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Abstract

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.

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Kou Takubo, Kohei Yamamoto, Yasuyuki Hirata, Yuichi Yokoyama, Yuya Kubota, Shingo Yamamoto, Susumu Yamamoto, Iwao Matsuda, Shik Shin, Takeshi Seki, Koki Takanashi, Hiroki Wadati. 2017-01-10. Capturing ultrafast magnetic dynamics by time-resolved soft x-ray magnetic circular dichroism. https://doi.org/10.1063/1.4981769

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