Tuning the Electronic Structure of Monolayer Graphene/MoS2 van der Waals Heterostructures via Interlayer Twist

Abstract

We directly measure the electronic structure of twisted graphene/MoS2 van der Waals heterostructures, in which both graphene and MoS2 are monolayers. We use cathode lens microscopy and microprobe angle-resolved photoemission spectroscopy measurements to image the surface, determine twist angle, and map the electronic structure of these artificial heterostructures. For monolayer graphene on monolayer MoS2, the resulting band structure reveals the absence of hybridization between the graphene and MoS2 electronic states. Further, the graphene-derived electronic structure in the heterostructures remains intact, irrespective of the twist angle between the two materials. In contrast, however, the electronic structure associated with the MoS2 layer is found to be twist-angle dependent; in particular, the relative difference in the energy of the valence band maximum at Γ and K of the MoS2 layer varies from approximately 0 to 0.2 eV. Our results suggest that monolayer MoS2 within the heterostructure becomes predominantly an indirect bandgap system for all twist angles except in the proximity of 30 degrees. This result enables potential bandgap engineering in van der Waals heterostructures comprised of monolayer structures.

arXiv comment20 pages including supplementary materials

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Cited by in corpus (8)

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• Electronic band structure of Two-Dimensional WS2/Graphene van der Waals Heterostructures
• Spatially Resolved Electronic Properties of Single-Layer WS${}_2$ on Transition Metal Oxides
• Highly Ordered Boron Nitride/Epigraphene Epitaxial Films on Silicon Carbide by Lateral Epitaxial Deposition
• ARPES signatures of few-layer twistronic graphenes
• Visualizing band structure hybridization and superlattice effects in twisted MoS${}_2$/WS${}_2$ heterobilayers
• Graphene Contacts to a HfSe2/SnS2 Heterostructure
• Proximity-induced topological transition and strain-induced charge transfer in graphene/MoS2 bilayer heterostructures