Observation of Electronic Strong Correlation in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>VTe</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mtext>-2</mml:mtext><mml:msqrt><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msqrt><mml:mo>×</mml:mo><mml:mn>2</mml:mn><mml:msqrt><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msqrt></mml:mrow></mml:math> Monolayer
Wei-Min Zhao, Wenjun Ding, Qiwei Wang, Yu-Xin Meng, Li Zhu, Zhen‐Yu Jia, Wenguang Zhu, Shao‐Chun Li
Abstract
Strong electron correlation under two-dimensional limit is intensely studied in the transition metal dichalcogenides monolayers, mostly within their charge density wave (CDW) states that host a star of David period. Here, by using scanning tunneling microscopy and spectroscopy and density functional theory calculations with on-site Hubbard corrections, we study the VTe_{2} monolayer with a different 2sqrt[3]×2sqrt[3] CDW period. We find that the dimerization of neighboring Te-Te and V-V atoms occurs during the CDW transition, and that the strong correlation effect opens a Mott-like full gap at Fermi energy (E_{F}). We further demonstrate that such a Mott phenomenon is ascribed to the combination of the CDW transition and on-site Coulomb interactions. Our work provides a new platform for exploring Mott physics in 2D materials.