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DOE OSTI · 1992873

Dirac nodal arc in 1T-VSe 2

Abstract

Transition metal dichalcogenides exhibit many fascinating properties including superconductivity, magnetic orders, and charge density wave. The combination of these features with a non-trivial band topology opens the possibility of additional exotic states such as Majorana fermions and quantum anomalous Hall effect. Here, we report on photon-energy and polarization dependent spin-resolved angle-resolved photoemission spectroscopy experiments on single crystal 1T-VSe 2 , revealing an unexpected band inversion and emergent Dirac nodal arc with spin-momentum locking. Density functional theory calculations suggest a surface lattice strain could be the driving mechanism for the topologically nontrivial electronic structure of 1T-VSe 2 .

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Yilmaz, Turgut, Jiang, Xuance, Lu, Deyu, Sheverdyaeva, Polina M., Matetskiy, Andrey V., Moras, Paolo, Mazzola, Federico, Vobornik, Ivana, Fujii, Jun, Evans-Lutterodt, Kenneth, Vescovo, Elio. 2023-06-23. Dirac nodal arc in 1T-VSe 2. https://doi.org/10.1038/s43246-023-00376-1

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36 MATERIALS SCIENCE↗