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arXiv · 2205.12417

Electronic properties of the steps in bilayer Td-WTe2

Mari Ohfuchi·Akihiko Sekine·Manabu Ohtomo·Kenichi Kawaguchi
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Abstract

Monolayer WTe2 stripes are quantum spin Hall (QSH) insulators. Density functional theory was used for investigating the electronic properties of the stripes and steps in bilayer Td-WTe2. For the stripes oriented along the dimer chains of W atoms (x direction), the hybridization between the two layers suppresses the QSH states. However, the QSH nature can be recovered by forming a step, depending on the atomic structure of the step. Conversely, the stripes and steps along the y direction maintain the QSH states. These findings can expand the application range of the QSH states in WTe2.

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Mari Ohfuchi, Akihiko Sekine, Manabu Ohtomo, Kenichi Kawaguchi. 2022-05-25. Electronic properties of the steps in bilayer Td-WTe2. https://doi.org/10.35848/1882-0786%2Fac6e29

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