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arXiv · 2110.15746

Optical spectroscopy and ultrafast pump-probe study of structural phase transition in 1T'-TaTe2

T. C. Hu·Q. Wu·Z. X. Wang·L. Y. Shi·Q. M. Liu·L. Yue·S. J. Zhang·R. S. Li·X. Y. Zhou·S. X. Xu·D. Wu·T. Dong·N. L. Wang
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Abstract

1T'-TaTe2 exhibits an intriguing first-order structural phase transition at around 170 K. Understanding the electronic structural properties is a crucial way to comprehend the origin of the structural phase transition. We performed a combined optical and ultrafast pump-probe study on the compound across the transition temperature. The phase transition leads to abrupt changes of both optical spectra and ultrafast electronic relaxation dynamics. The measurements revealed a sudden reconstruction of band structure. We elaborate that the phase transition is of the first order and can not be attributed to the conventional density-wave type instability. Our work is illuminating for understanding the origin of the structural phase transition.

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T. C. Hu, Q. Wu, Z. X. Wang, L. Y. Shi, Q. M. Liu, L. Yue, S. J. Zhang, R. S. Li, X. Y. Zhou, S. X. Xu, D. Wu, T. Dong, N. L. Wang. 2021-10-29. Optical spectroscopy and ultrafast pump-probe study of structural phase transition in 1T'-TaTe2. https://doi.org/10.1103/physrevb.105.075113

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