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arXiv · 1905.04120

Study of photoinduced valence dynamics in EuNi$_2$(Si$_{0.21}$Ge$_{0.79}$)$_2$ through time-resolved X-ray absorption spectroscopy

Y. Yokoyama·K. Kawakami·Y. Hirata·K. Takubo·K. Yamamoto·K. Abe·A. Mitsuda·H. Wada·T. Uozumi·S. Yamamoto·I. Matsuda·K. Mimura·H. Wadati
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Abstract

The photoinduced valence dynamics of EuNi$_2$(Si$_{0.21}$Ge$_{0.79}$)$_2$ are investigated using time-resolved X-ray absorption spectroscopy for Eu $M_5$-edge. Through the pump-probe technique with synchrotron X-ray and Ti:sapphire laser pulse, a photoinduced valence transition is observed from Eu$^{3+}$ to Eu$^{2+}$. Because the lifetime of a photoinduced state can be up to 3 ns, a metastable state is considered to be realized. By comparing the experimental results with the theoretical calculations, the photoinduced valence transition between Eu 4$f$ and conduction electrons is quantitatively evaluated.

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Y. Yokoyama, K. Kawakami, Y. Hirata, K. Takubo, K. Yamamoto, K. Abe, A. Mitsuda, H. Wada, T. Uozumi, S. Yamamoto, I. Matsuda, K. Mimura, H. Wadati. 2019-05-10. Study of photoinduced valence dynamics in EuNi$_2$(Si$_{0.21}$Ge$_{0.79}$)$_2$ through time-resolved X-ray absorption spectroscopy. https://doi.org/10.1103/physrevb.100.115123

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