By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.
|Original language||English (US)|
|Number of pages||7|
|State||Published - Sep 25 2015|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This research was supported with grants from the Welch Foundation (F-1672), and the U.S. National Science Foundation (DMR-1306878 and DMR-1205275). L.J.L. thanks the support from Academia Sinica Taiwan, AOARD-134137 U.S.A. and KAUST, Saudi Arabia. C.K.S also thanks the partially supported by the NT 3.0 Program, Ministry of Education, Taiwan for a visitng professorship at the National Tsing-Hua University. We also thank useful discussions with Professor Wang Yao of Hong Kong University.