Scanning tunneling spectroscopic study of monolayer 1T-TaS2 and 1T-TaSe2
monolayer, 1T-TaS2, 1T-TaSe2, commensurate charge density wave (CCDW), Mott gap, band insulator
The isostructural and isoelectronic transition-metal-dichalcogenides 1T-TaS2 and 1T-TaSe2 are layered materials with intricate electronic structures. Combining the molecular beam epitaxy growth, scanning tunneling microscopy measurements and firstprinciples calculations, we prepare monolayer 1T-TaS2 and TaSe2 and explore their electronic structures at the atomic scale. Both two-dimensional (2D) compounds exhibit commensurate charge density wave phase at low temperature. The conductance mapping identifies the contributions from different Ta atoms to the local density of states with spatial and energy resolution. Both 1T-TaS2 and 1T-TaSe2 monolayer are shown to be insulators, while the former has a Mott gap and the latter is a regular band insulator.
Tsinghua University Press
Haicheng Lin,Wantong Huang,Kun Zhao,Shuang Qiao,Zheng Liu,Jian Wu,Xi Chen,Shuai-Hua Ji, Scanning tunneling spectroscopic study of monolayer 1T-TaS2 and 1T-TaSe2. NanoRes.2020, 13(1): 133–137