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arXiv · 2105.10083

Photo-induced Antiferromagnetic-ferromagnetic Transition and Electronic Structure Modulation in GdBaCo$_2$O$_{5.5}$ Thin Film

Yujun Zhang·Tsukasa Katayama·Akira Chikamatsu·Christian Schüßler-Langeheine·Niko Pontius·Yasuyuki Hirata·Kou Takubo·Kohei Yamagami·Keisuke Ikeda·Kohei Yamamoto·Tetsuya Hasegawa·Hiroki Wadati
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Abstract

We investigate both the ferromagnetic (FM) and antiferromagnetic (AFM) ultrafast dynamics of a strongly correlated oxide system, GdBaCo$_2$O$_{5.5}$ thin film, by time-resolved x-ray magnetic circular dichroism in reflectivity (XMCDR) and resonant magnetic x-ray diffraction (RMXD). A photo-induced AFM-FM transition characterized by an increase of the transient XMCDR beyond the unpumped value and a decay of RMXD was observed. The photon-energy dependence of the transient XMCDR and reflectivity can likely be interpreted as a concomitant photo-induced spinstate transition.

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Yujun Zhang, Tsukasa Katayama, Akira Chikamatsu, Christian Schüßler-Langeheine, Niko Pontius, Yasuyuki Hirata, Kou Takubo, Kohei Yamagami, Keisuke Ikeda, Kohei Yamamoto, Tetsuya Hasegawa, Hiroki Wadati. 2021-05-21. Photo-induced Antiferromagnetic-ferromagnetic Transition and Electronic Structure Modulation in GdBaCo$_2$O$_{5.5}$ Thin Film. https://doi.org/10.1038/s42005-022-00823-4

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