Direct observation of topological surface state in the topological superconductor 2M-WS2

Abstract

The quantum spin Hall (QSH) effect has attracted extensive research interest because of the potential applications in spintronics and quantum computing, which is attributable to two conducting edge channels with opposite spin polarization and the quantized electronic conductance of 2e2/h. Recently, 2M-WS2, a new stable phase of transition metal dichalcogenides with a 2M structure showing an identical layer configuration to that of the monolayer 1T' TMDs, was suggested to be a QSH insulator as well as a superconductor with critical transition temperature around 8 K. Here, high-resolution angle-resolved photoemission spectroscopy (ARPES) and spin-resolved ARPES are applied to investigate the electronic and spin structure of the topological surface states (TSS) in the superconducting 2M-WS2. The TSS exhibits characteristic spin-momentum-locking behavior, suggesting the existence of long-sought nontrivial Z2 topological states therein. We expect that 2M-WS2 with co-existing superconductivity and TSS might host the promising Majorana bound states.

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• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Observation of the Quantum Spin Hall Effect up to 100 Kelvin in a Monolayer Crystal
• Discovery of a new type of topological Weyl fermion semimetal state in Mo${}_x$W${}_{1-x}$Te${}_2$
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Cited by in corpus (6)

• Crossover from Conventional to Unconventional Superconductivity in 2M-WS2
• Anisotropic multiband superconductivity in 2M-WS${}_2$ probed by controlled disorder
• Tunable superconductivity coexisting with the anomalous Hall effect in 1T'-WS2
• Visualization of Unconventional Rashba Band and Vortex Zero Mode in Topopogical Superconductor Candidate AuSn${}_4$
• Lattice-decoupled rotatable stripe-like charge order within the strange metal phase of 2M-WS2
• One-Dimensional Spin-Polarised Surface States -- A Comparison of Bi(112) with Other Vicinal Bismuth Surfaces