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arXiv · 2001.05649

Orbital-collaborative Charge Density Wave in Monolayer VTe2

Qiucen Wu·Zhongjie Wang·Yucheng Guo·Fang Yang·Chunlei Gao
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Abstract

Charge density waves in transition metal dichalcogenides have been intensively studied for their close correlation with Mott insulator, charge-transfer insulator, and superconductor. VTe2 monolayer recently comes into sight because of its prominent electron correlations and the mysterious origin of CDW orders. As a metal of more than one type of charge density waves, it involves complicated electron-electron and electron-phonon interactions. Through a scanning tunneling microscopy study, we observed triple-Q 4-by-4 and single-Q 4-by-1 modulations with significant charge and orbital separation. The triple-Q 4-by-4 order arises strongly from the p-d hybridized states, resulting in a charge distribution in agreement with the V-atom clustering model. Associated with a lower Fermi level, the local single-Q 4-by-1 electronic pattern is generated with the p-d hybridized states remaining 4-by-4 ordered. In the spectroscopic study, orbital- and atomic- selective charge-density-wave gaps with the size up to ~400 meV were resolved on the atomic scale.

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Qiucen Wu, Zhongjie Wang, Yucheng Guo, Fang Yang, Chunlei Gao. 2020-01-16. Orbital-collaborative Charge Density Wave in Monolayer VTe2. https://doi.org/10.1103/physrevb.101.205105

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