Visualizing Band Offsets and Edge States in Bilayer-Monolayer Transition Metal Dichalcogenides Lateral Heterojunction

Abstract

Semiconductor heterostructures are fundamental building blocks for many important device applications. The emergence of two-dimensional semiconductors opens up a new realm for creating heterostructures. As the bandgaps of transition metal dichalcogenides thin films have sensitive layer dependence, it is natural to create lateral heterojunctions using the same materials with different thicknesses. Using scanning tunneling microscopy and spectroscopy, here we show the real space image of electronic structures across the bilayer-monolayer interface in MoSe2 and WSe2. Most bilayer-monolayer heterojunctions are found to have a zigzag-orientated interface, and the band alignment of such atomically sharp heterojunctions is of type-I with a well-defined interface mode which acts as a narrower-gap quantum wire. The ability to utilize such commonly existing thickness terrace as lateral heterojunctions is a crucial addition to the tool set for device applications based on atomically thin transition metal dichalcogenides, with the advantage of easy and flexible implementation.

arXiv comment19 pages in total, 4 figures and 1 table

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• Band alignment of two-dimensional lateral heterostructures
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• The Role of Odd-Frequency Pairing in Multiband Superconductors
• Controlled Growth of Large-Area Bilayer Tungsten Diselenides with Lateral P-N Junctions
• Lateral heterostructures and one-dimensional interfaces in 2D transition metal dichalcogenides
• Band Bending and Valence Band Quantization at Line Defects in MoS${}_2$
• Experimental Progress on Layered Topological Semimetals
• Lateral Interfaces of Transition Metal Dichalcogenides: A Stable Tunable One-Dimensional Physics Platform
• Coexistence of electron whispering-gallery modes and atomic collapse states in graphene WSe2 heterostructure quantum dots
• Energy-resolved Photoconductivity Mapping in a Monolayer-bilayer WSe2 Lateral Heterostructure
• Bound hole states associated to individual vanadium atoms incorporated into monolayer WSe${}_2$
• Semiconducting van der Waals Interfaces as Artificial Semiconductors
• Lateral transition metal dichalcogenide heterostructures for high efficiency thermoelectric devices
• Atomically Resolved Observation of Continuous Interfaces between As-grown MoS2 Monolayer and WS2/MoS2 Heterobilayer on SiO2
• Anomalous Bloch oscillation and electrical switching of edge magnetization in bilayer graphene nanoribbon
• Spin and valley filter based on two-dimensional WSe${}_2$ heterostructures
• Theoretical Analysis of a Two-Dimensional Metallic/Semiconducting Transition-Metal Dichalcogenide NbS2//WSe2 Hybrid Interface