@article{add60037de5f4c97ba3806352a5b2aad,
title = "Charge order with unusual star-of-David lattice in monolayer NbTe2",
abstract = "Interplay between fermiology and electron correlation is crucial for realizing exotic quantum phases. Transition-metal dichalcogenide (TMD) 1T-TaS2 has sparked tremendous attention owing to its unique Mott-insulating phase coexisting with the charge-density wave (CDW). However, how the fermiology and electron correlation are associated with such properties has yet to be clarified. Here we demonstrate that monolayer 1T-NbTe2 is a new class of two-dimensional TMD which has the star-of-David lattice similarly to bulk TaS2 and isostructural monolayer NbSe2, but exhibits a metallic ground state with an unusual lattice periodicity (19×19) characterized by the sparsely occupied star-of-David lattice. By using angle-resolved photoemission and scanning-tunneling spectroscopies in combination with first-principles band-structure calculations, we found that the hidden Fermi-surface nesting and associated CDW formation are a primary cause to realize this unique correlated metallic state with no signature of Mott gap. The present result points to a vital role of underlying fermiology to characterize the Mott phase of TMDs.",
author = "Taiki Taguchi and Katsuaki Sugawara and Hirofumi Oka and Tappei Kawakami and Yasuaki Saruta and Takemi Kato and Kosuke Nakayama and Seigo Souma and Takashi Takahashi and Tomoteru Fukumura and Takafumi Sato",
note = "Funding Information: We thank Y. Nakata, M. Kitamura, K. Horiba, and H. Kumigashira for their help in the ARPES experiments. This work was supported by JST-CREST (Grant No. JPMJCR18T1), JST-PRESTO (Grant No. JPMJPR20A8), Grant-in-Aid for Scientific Research on Innovative Areas “Topological Materials Science” (JSPS KAKENHI Grants No. JP15H05853 and No. JP15K21717), Grant-in-Aid for Scientific Research on Innovative Areas “Discrete Geometric Analysis for Materials Design” (JSPS KAKENHI Grant No. 20H04624), Grant-in-Aid for Scientific Research (JSPS KAKENHI Grants No. JP18H01821 and No. JP21H01757), Science research projects from Shimadzu Science Foundation, and World Premier International Research Center, Advanced Institute for Materials Research. T. Kawakami and T. Kato acknowledge support from GP-Spin at Tohoku University. Publisher Copyright: {\textcopyright} 2023 American Physical Society. ",
year = "2023",
month = jan,
day = "15",
doi = "10.1103/PhysRevB.107.L041105",
language = "English",
volume = "107",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "4",
}