Quantum spin Hall state in monolayer 1T'-WTe2
- Author(s): Tang, S
- Zhang, C
- Wong, D
- Pedramrazi, Z
- Tsai, HZ
- Jia, C
- Moritz, B
- Claassen, M
- Ryu, H
- Kahn, S
- Jiang, J
- Yan, H
- Hashimoto, M
- Lu, D
- Moore, RG
- Hwang, CC
- Hwang, C
- Hussain, Z
- Chen, Y
- Ugeda, MM
- Liu, Z
- Xie, X
- Devereaux, TP
- Crommie, MF
- Mo, SK
- Shen, ZX
- et al.
Published Web Location
https://doi.org/10.1038/nphys4174Abstract
A quantum spin Hall (QSH) insulator is a novel two-dimensional quantum state of matter that features quantized Hall conductance in the absence of a magnetic field, resulting from topologically protected dissipationless edge states that bridge the energy gap opened by band inversion and strong spin-orbit coupling. By investigating the electronic structure of epitaxially grown monolayer 1T'-WTe2using angle-resolved photoemission (ARPES) and first-principles calculations, we observe clear signatures of topological band inversion and bandgap opening, which are the hallmarks of a QSH state. Scanning tunnelling microscopy measurements further confirm the correct crystal structure and the existence of a bulk bandgap, and provide evidence for a modified electronic structure near the edge that is consistent with the expectations for a QSH insulator. Our results establish monolayer 1T'-WTe2as a new class of QSH insulator with large bandgap in a robust two-dimensional materials family of transition metal dichalcogenides (TMDCs).
Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.