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DOE OSTI · 3378237

Ultrafast One-Dimensional Peierls-Distortion Dynamics in 1⁢T′−Re⁢S 2 Revealed by 4D Electron Microscopy

Abstract

Rhenium disulfide (ReS 2 ), a prototypical 2D semiconductor with an anisotropic 1⁢T′ structure due to the pronounced Peierls distortion, has demonstrated great potential for polarization-dependent optoelectronics and photonics. Here, we report an ultrafast phase transition occurring within 1 ps, accompanied by a one-dimensional Peierls-distortion relaxation in 1⁢T′−ReS 2 revealed with combined 4D electron microscopy and time-dependent density functional theory calculations. Upon femtosecond laser pulse excitation, the Re-Re dimerization morphology rapidly transforms from a diamond cluster to zigzag chains and persists for several nanoseconds. Here, this ultrafast Peierls-distortion relaxation is further verified by transient changes in optical anisotropy via polarization-dependent transient absorption spectroscopy. Time-dependent density functional theory calculations attribute this novel phase transition to strong correlation between Peierls distortion and impulsive photoexcited carrier doping, predicting a transient band-gap collapse. This Letter opens up an exciting avenue for ultrafast control of Peierls-distortion-induced anisotropy and the metal-insulator transition in 1⁢T′−ReS 2 .

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Liu, Jingchao [Nankai University, Tianjin (China)] (ORCID:0000000271028823), Ji, Shaozheng [Nankai University, Tianjin (China)] (ORCID:0000000328998725), Zhang, Lifu [Tianjin Medical University (China)] (ORCID:0009000660809567), Jiao, Yiping [Nankai University, Tianjin (China)] (ORCID:0009000670375571), Guo, Jiangteng [Nankai University, Tianjin (China)], Gao, Cuntao [Nankai University, Tianjin (China)], Liu, Fang [Nankai University, Tianjin (China)], Deng, Shibin [Nankai University, Tianjin (China)] (ORCID:0000000218778078), Cao, Xuewei [Nankai University, Tianjin (China)], Hu, Zhenpeng [Nankai University, Tianjin (China)] (ORCID:0000000284691683), Zhu, Yimei [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000216387217), Fu, Xuewen [Nankai University, Tianjin (China)] (ORCID:0000000161164680). 2026-03-02. Ultrafast One-Dimensional Peierls-Distortion Dynamics in 1⁢T′−Re⁢S 2 Revealed by 4D Electron Microscopy. https://doi.org/10.1103/mygw-t2br

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