Proximity-induced superconducting gap in the quantum spin Hall edge state of monolayer WTe2

@article{Lpke2020ProximityinducedSG,
  title={Proximity-induced superconducting gap in the quantum spin Hall edge state of monolayer WTe2},
  author={Felix L{\"u}pke and Dacen Waters and Sergio C. de la Barrera and Michael Widom and David G. Mandrus and Jiaqiang Yan and Randall M. Feenstra and Benjamin M. Hunt},
  journal={Nature Physics},
  year={2020}
}
The quantum spin Hall (QSH) state was recently demonstrated in monolayers of the transition metal dichalcogenide 1T'-WTe$_2$ and is characterized by a band gap in the two-dimensional (2D) interior and helical one-dimensional (1D) edge states. Inducing superconductivity in the helical edge states would result in a 1D topological superconductor, a highly sought-after state of matter. In the present study, we use a novel dry-transfer flip technique to place atomically-thin layers of WTe$_2$ on a… 
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