Projects per year
Abstract
Several transition-metal dichalcogenides exhibit a striking crossover from indirect to direct band gap semiconductors as they are thinned down to a single monolayer. Here, we demonstrate how an electronic structure characteristic of the isolated monolayer can be created at the surface of a bulk MoS2 crystal. This is achieved by intercalating potassium in the interlayer van der Waals gap, expanding its size while simultaneously doping electrons into the conduction band. Our angle-resolved photoemission measurements reveal resulting electron pockets centered at the (K) over bar and (K') over bar points of the Brillouin zone, providing the first momentum-resolved measurements of how the conduction band dispersions evolve to yield an approximately direct band gap of 1.8 eV in quasi-freestanding monolayer MoS2. As well as validating previous theoretical proposals, this establishes a novel methodology for manipulating electronic structure in transition-metal dichalcogenides, opening a new route for the generation of large-area quasi-freestanding monolayers for future fundamental study and use in practical applications.
Original language | English |
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Pages (from-to) | 1312-1316 |
Number of pages | 5 |
Journal | Nano Letters |
Volume | 14 |
Issue number | 3 |
Early online date | 19 Feb 2014 |
DOIs | |
Publication status | Published - 12 Mar 2014 |
Keywords
- Molybdenum disulfide (MoS2)
- Transition metal dichalcogenides (TMD)
- Layered semiconductor
- Electronic structure
- Angle-resolved photoemission
- van der Waals expansion
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Dive into the research topics of 'Electronic structure of a quasi-freestanding MoS2 monolayer'. Together they form a unique fingerprint.Projects
- 3 Finished
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Royal Society Research Fellowship: Electronic structure engineering of novel topological phases
King, P. (PI)
1/10/13 → 30/09/18
Project: Fellowship
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Topological Protection and NonEquilibriu: Topological Protection and NonEquilibrium States in Strongly Correlated Electron Systems
Wahl, P. (PI), Baumberger, F. (CoI), Davis, J. C. (CoI), Green, A. (CoI), Hooley, C. (CoI), Keeling, J. M. J. (CoI) & Mackenzie, A. (CoI)
1/09/11 → 31/08/17
Project: Standard
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Laser-ARPES: Laser based photoelectron spectroscopy for a closer look at correlated electrons
Baumberger, F. (PI)
1/08/08 → 31/07/13
Project: Standard