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arXiv · 1909.06791

Valence-selective local atomic structures on a YbInCu4 valence transition material by x-ray fluorescence holography

Shinya Hosokawa·Naohisa Happo·Kouichi Hayashi·Koji Kimura·Tomohiro Matsushita·Jens Rüdiger Stellhorn·Masaichiro Mizumaki·Motohiro Suzuki·Hitoshi Sato·Koichi Hiraoka
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Abstract

An experimental technique of x-ray fluorescence holography for investigating valence-selective local structures was established by employing the incident x-ray energy at a characteristic one near an x-ray absorption edge, and it was adopted to discriminate environments around Yb2+ and Yb3+ ions in a YbInCu4 valence transition material below and above the transition temperature of 42 K. The reconstructed images of the neighboring atoms around Yb3+ show a fcc structure as observed by diffraction experiments, whereas those around Yb2+ have curious cross (+) features, indicating a positional shift of the centered Yb2+ ions from the fcc lattice point.

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Shinya Hosokawa, Naohisa Happo, Kouichi Hayashi, Koji Kimura, Tomohiro Matsushita, Jens Rüdiger Stellhorn, Masaichiro Mizumaki, Motohiro Suzuki, Hitoshi Sato, Koichi Hiraoka. 2019-09-15. Valence-selective local atomic structures on a YbInCu4 valence transition material by x-ray fluorescence holography. https://doi.org/10.7567/1347-4065%2Fab5258

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