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arXiv · 2004.07455

Two phase transitions driven by surface electron-doping in WTe$_2$

Antonio Rossi·Giacomo Resta·Seng Huat Lee·Ronald Dean Redwing·Chris Jozwiak·Aaron Bostwick·Eli Rotemberg·Sergey Y. Savrasov·Inna M. Vishik
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Abstract

WTe$_2$ is a multifunctional quantum material exhibiting numerous emergent phases in which tuning of the carrier density plays an important role. Here we demonstrate two non-monotonic changes in the electronic structure of WTe$_2$ upon \textit{in-situ} electron doping. The first phase transition is interpreted in terms of a shear displacement of the top WTe$_2$ layer, which realizes a local crystal structure not normally found in bulk WTe$_2$. The second phase transition is associated with stronger interactions between the dopant atoms and the host, both through hybridization and electric field. These results demonstrate that electron-doping can drive structural and electronics changes in bulk WTe$_2$ with implications for realizing nontrivial band structure changes in heterointerfaces and devices.

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Antonio Rossi, Giacomo Resta, Seng Huat Lee, Ronald Dean Redwing, Chris Jozwiak, Aaron Bostwick, Eli Rotemberg, Sergey Y. Savrasov, Inna M. Vishik. 2020-07-02. Two phase transitions driven by surface electron-doping in WTe$_2$. https://doi.org/10.1103/physrevb.102.121110

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