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arXiv · 2211.01501

A light-induced Weyl semiconductor-to-metal transition mediated by Peierls instability

H. Ning·O. Mehio·C. Lian·X. Li·E. Zoghlin·P. Zhou·B. Cheng·S. D. Wilson·B. M. Wong·D. Hsieh
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Abstract

Elemental tellurium is a strongly spin-orbit coupled Peierls-distorted semiconductor whose band structure features topologically protected Weyl nodes. Using time-dependent density functional theory calculations, we show that impulsive optical excitation can be used to transiently control the amplitude of the Peierls distortion, realizing a mechanism to switch tellurium between three states: Weyl semiconductor, Weyl metal and non-Weyl metal. Further, we present experimental evidence of this inverse-Peierls distortion using time-resolved optical second harmonic generation measurements. These results provide a pathway to multifunctional ultrafast Weyl devices and introduce Peierls systems as viable hosts of light-induced topological transitions.

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H. Ning, O. Mehio, C. Lian, X. Li, E. Zoghlin, P. Zhou, B. Cheng, S. D. Wilson, B. M. Wong, D. Hsieh. 2022-11-02. A light-induced Weyl semiconductor-to-metal transition mediated by Peierls instability. https://doi.org/10.1103/physrevb.106.205118

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