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DOE OSTI · 1713259

Two phase transitions driven by surface electron doping in WTe 2

Rossi, Antonio·Resta, Giacomo·Lee, Seng Huat·Redwing, Ronald Dean·Jozwiak, Chris·Bostwick, Aaron·Rotenberg, Eli·Savrasov, Sergey Y.·Vishik, Inna M.
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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. In this work, we demonstrate two nonmonotonic changes in the electronic structure of WTe 2 upon 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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BibTeXRIS

Rossi, Antonio, Resta, Giacomo, Lee, Seng Huat, Redwing, Ronald Dean, Jozwiak, Chris, Bostwick, Aaron, Rotenberg, Eli, Savrasov, Sergey Y., Vishik, Inna M.. 2020-09-30. Two phase transitions driven by surface electron doping in WTe 2. https://doi.org/10.1103/physrevb.102.121110

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