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arXiv · 2105.13146

Suppression of atomic displacive excitation in photo-induced A$_{\mathrm{1g}}$ phonon mode of bismuth unveiled by low-temperature time-resolved x-ray diffraction

Y. Kubota·Yoshikazu Tanaka·T. Togashi·T. Ebisu·K. Tamasaku·H. Osawa·T. Wada·O. Sugino·I. Matsuda·M. Yabashi
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Abstract

An ultrafast atomic motion of a photo-induced coherent phonon of bismuth at low temperatures was directly observed with time-resolved x-ray diffraction. A cryostat with a window that is transparent to both optical lasers and x-rays enabled versatile diffraction measurements in a wide temperature range including below 10 K. It is found that an atomic displacement in a fully symmetric A$_{\mathrm{1g}}$ phonon mode is suppressed at low temperatures. This result indicates the displacive excitation process is suppressed in the phonon generation with decreasing temperature.

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Y. Kubota, Yoshikazu Tanaka, T. Togashi, T. Ebisu, K. Tamasaku, H. Osawa, T. Wada, O. Sugino, I. Matsuda, M. Yabashi. 2021-05-27. Suppression of atomic displacive excitation in photo-induced A$_{\mathrm{1g}}$ phonon mode of bismuth unveiled by low-temperature time-resolved x-ray diffraction. https://doi.org/10.1063/5.0136787

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