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arXiv · 2305.17329

Ultrafast Control of Crystal Structure in a Topological Charge-Density-Wave Material

Takeshi Suzuki·Yuya Kubota·Natsuki Mitsuishi·Shunsuke Akatsuka·Jumpei Koga·Masato Sakano·Satoru Masubuchi·Yoshikazu Tanaka·Tadashi Togashi·Hiroyuki Ohsumi·Kenji Tamasaku·Makina Yabashi·Hidefumi Takahashi·Shintaro Ishiwata·Tomoki Machida·Iwao Matsuda·Kyoko Ishizaka·Kozo Okazaki
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Abstract

Optical control of crystal structures is a promising route to change physical properties including topological nature of a targeting material. Time-resolved X-ray diffraction measurements using the X-ray free-electron laser are performed to study the ultrafast lattice dynamics of VTe$_2$, which shows a unique charge-density-wave (CDW) ordering coupled to the topological surface states as a first-order phase transition. A significant oscillation of the CDW amplitude mode is observed at a superlattice reflection as well as Bragg reflections. The frequency of the oscillation is independent of the fluence of the pumping laser, which is prominent to the CDW ordering of the first-order phase transition. Furthermore, the timescale of the photoinduced 1$T^{\prime\prime}$ to 1$T$ phase transition is independent of the period of the CDW amplitude mode.

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Takeshi Suzuki, Yuya Kubota, Natsuki Mitsuishi, Shunsuke Akatsuka, Jumpei Koga, Masato Sakano, Satoru Masubuchi, Yoshikazu Tanaka, Tadashi Togashi, Hiroyuki Ohsumi, Kenji Tamasaku, Makina Yabashi, Hidefumi Takahashi, Shintaro Ishiwata, Tomoki Machida, Iwao Matsuda, Kyoko Ishizaka, Kozo Okazaki. 2023-05-27. Ultrafast Control of Crystal Structure in a Topological Charge-Density-Wave Material. https://doi.org/10.1103/physrevb.108.184305

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