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arXiv · 2404.08256

Unusual photoinduced crystal structure dynamics in TaTe$_2$ with double zigzag chain superstructure

J. Koga·Y. Chiashi·A. Nakamura·T. Akiba·H. Takahashi·T. Shimojima·S. Ishiwata·K. Ishizaka
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Abstract

Transition metal dichalcogenides with superperiodic lattice distortions have been widely investigated as the platform of ultrafast structural phase manipulations. Here we performed ultrafast electron diffraction on room-temperature TaTe$_2$, which exhibits peculiar double zigzag chain pattern of Ta atoms. From the time-dependent electron diffraction pattern, we revealed a photoinduced change in the crystal structure occurring within <0.5 ps, though there is no corresponding high-temperature equilibrium phase. We further clarified the slower response (~1.5 ps) reflecting the lattice thermalization. Our result suggests the unusual ultrafast crystal structure dynamics specific to the non-equilibrium transient process in TaTe$_2$.

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J. Koga, Y. Chiashi, A. Nakamura, T. Akiba, H. Takahashi, T. Shimojima, S. Ishiwata, K. Ishizaka. 2024-04-12. Unusual photoinduced crystal structure dynamics in TaTe$_2$ with double zigzag chain superstructure. https://doi.org/10.35848/1882-0786%2Fad3b61

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