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arXiv · 2107.03810

Electronic states of multilayer VTe2: quasi-one-dimensional Fermi surface and implications to charge-density waves

T. Kawakami·K. Sugawara·T. Kato·T. Taguchi·S. Souma·T. Takahashi·T. Sato
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Abstract

We have performed angle-resolved photoemission spectroscopy on epitaxial VTe2 films to elucidate the relationship between the fermiology and charge-density waves (CDW). We found that a two-dimensional triangular pocket in 1 monolayer (ML) VTe2 is converted to a strongly warped quasi-one-dimensional (1D) Fermi surface in the 6ML counterpart, likely associated with the 1T-to-1T' structural phase transition. We also revealed a metallic Fermi edge on the entire Fermi surface in 6ML at low temperature distinct from anisotropic pseudogap in 1ML, signifying a contrast behavior of CDW that is also supported by first-principles band-structure caluculations. The present result points to the importance of simultaneously controlling the structural phase and fermiology to manipulate the CDW properties in ultrathin transition-metal dichalcogenides.

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T. Kawakami, K. Sugawara, T. Kato, T. Taguchi, S. Souma, T. Takahashi, T. Sato. 2021-07-08. Electronic states of multilayer VTe2: quasi-one-dimensional Fermi surface and implications to charge-density waves. https://doi.org/10.1103/physrevb.104.045136

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