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DOE OSTI · 1906458

Electronic structure and charge-density wave transition in monolayer $\mathrm{VS}_2$

Kim, Hyuk Jin·Choi, Byoung Ki·Lee, In Hak·Kim, Min Jay·Chun, Seung-Hyun·Jozwiak, Chris·Bostwick, Aaron·Rotenberg, Eli·Chang, Young Jun
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Abstract

Vanadium disulfide (VS 2 ) attracts elevated interests for its charge-density wave (CDW) phase transition, ferromagnetism, and catalytic reactivity, but the electronic structure of monolayer has not been well understood yet. Here we report synthesis of epitaxial 1T VS 2 monolayer on bilayer graphene grown by molecular-beam epitaxy (MBE). Angle-resolved photoemission spectroscopy (ARPES) measurements reveal that Fermi surface with six elliptical pockets centered at the M points shows gap opening at low temperature. Temperature-dependence of the gap size suggests existence of CDW phase transition above room temperature. Here, our observations provide important evidence to understand the strongly correlated electron physics and the related surface catalytic properties in two-dimensional transition-metal dichalcogenides (TMDCs).

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSangle-resolved photoemission spectroscopycharge-density wavemolecular-beam epitaxytransition-metal dichalcogenidevanadium disulfide

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Kim, Hyuk Jin, Choi, Byoung Ki, Lee, In Hak, Kim, Min Jay, Chun, Seung-Hyun, Jozwiak, Chris, Bostwick, Aaron, Rotenberg, Eli, Chang, Young Jun. 2021-04-07. Electronic structure and charge-density wave transition in monolayer $\mathrm{VS}_2$. https://doi.org/10.1016/j.cap.2021.03.020

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