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arXiv · 2406.16663

Light-induced percolative topological phase transition in type-II Weyl semimetal WTe2

Xiaoyue Zhou·Fu Deng·Yifan Gao·Yi Chan·Shulei Li·Ning Wang·Junwei Liu·Jingdi Zhang
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Abstract

We report on an ultrafast terahertz free-carrier dynamic study of a photo-excited WTe2 thin film. In the photo-excited state, we observe a metastable electronic state featuring negative differential terahertz photoconductivity and reduced scattering rate. Detailed electrodynamics analysis and first-principal calculation attribute it to light-induced topological phase transition, reducing density of states near the Fermi level. Furthermore, the emergence of an unconventional temporal isosbestic point marks a dynamic universality, strongly suggesting a percolative interaction between the two topologically distinct phases.

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Xiaoyue Zhou, Fu Deng, Yifan Gao, Yi Chan, Shulei Li, Ning Wang, Junwei Liu, Jingdi Zhang. 2024-09-02. Light-induced percolative topological phase transition in type-II Weyl semimetal WTe2. https://arxiv.org/abs/2406.16663

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