Multi band Fermi surface in 1T-VSe2 and its implication for charge density wave phase

TL;DR

This study uses angle resolved photoemission spectroscopy to reveal a complex multi-band Fermi surface in 1T-VSe2, challenging previous assumptions about its electronic structure and charge density wave phase.

Contribution

It uncovers previously unobserved surface electronic states and clarifies the nature of the Fermi surface, prompting a reevaluation of charge density wave effects in 1T-VSe2.

Findings

Surface band structure hosts unpredicted electronic states

Fermi surface is not gapped at any Brillouin zone point

Warpage effects are due to multiple band dispersions

Abstract

Here, our angle resolved photoemission spectroscopy experiment reveled that the surface band structure of the 1T-VSe2 host electronic states that was not predicted or probed before. Earlier claims to support charge density wave phase can be all explained in terms of these new findings. Its Fermi surface found to be not gaped at any point of the Brillouin zone and warping effect on the electronic structure, attributed to the lattice distortion previously, is due to the different dispersion of the multiple bands. Based on these new findings and interpretations, charge density wave induced modification on the electronic structure of 1T-VSe2 needs to be reconstructed in the future studies.