Electronic Janus lattice and kagome-like bands in coloring-triangular MoTe2 monolayers
Nature Communications 14, 6320 (2023).
Le Lei#, Jiaqi Dai#, Haoyu Dong#, Yanyan Geng, Feiyue Cao, Cong Wang, Rui Xu, Fei Pang, Zheng-Xin Liu, Fangsen Li, Zhihai Cheng*, Guang Wang* and Wei Ji*
Abstract: Polymorphic structures of transition metal dichalcogenides (TMDs) host exotic electronic states, like charge density wave and superconductivity. However, the number of these structures is limited by crystal symmetries, which poses a challenge to achieving tailored lattices and properties both theoretically and experimentally. Here, we report a coloring triangle (CT) latticed MoTe2 monolayer, termed CT-MoTe2, constructed by controllably introducing uniform and ordered mirror-twin-boundaries into a pristine monolayer in molecular beam epitaxy. Low-temperature scanning tunneling microscopy and spectroscopy (STM/STS) together with theoretical calculations reveal that the monolayer has an electronic Janus lattice, i.e., an energy-dependent atomic-lattice and a Te pseudo-sublattice, and shares the identical geometry with the Mo5Te8 layer. Dirac-like and flat electronic bands inherently existing in the CT lattice are identified by two broad and two prominent peaks in STS spectra, respectively, and verified with density-functional-theory calculations. Two types of intrinsic domain boundaries were observed, one of which the electronic-Janus-lattice feature maintains, implying potential applications as an energy-tunable electron-tunneling barrier in future functional devices.
DOI: 10.1038/s41467-023-42044-5; arXiv:2302.06166
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