Direct STM Measurements of R- and H-type Twisted MoSe2/WSe2 Heterostructures

Abstract

When semiconducting transition metal dichalcogenides heterostructures are stacked the twist angle and lattice mismatch leads to a periodic moiré potential. As the angle between the layers changes, so do the electronic properties. As the angle approaches 0- or 60-degrees interesting characteristics and properties such as modulations in the band edges, flat bands, and confinement are predicted to occur. Here we report scanning tunneling microscopy and spectroscopy measurements on the band gaps and band modulations in MoSe2/WSe2 heterostructures with near 0 degree rotation (R-type) and near 60 degree rotation (H-type). We find a modulation of the band gap for both stacking configurations with a larger modulation for R-type than for H-type as predicted by theory. Furthermore, local density of states images show that electrons are localized differently at the valence band and conduction band edges.

Published version

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Cited by in corpus (7)

• Hofstadter states and reentrant charge order in a semiconductor moiré lattice
• Metal-insulator transition in transition metal dichalcogenide heterobilayer: accurate treatment of interaction
• Signatures of electric field and layer separation effects on the spin-valley physics of MoSe${}_2$/WSe${}_2$ heterobilayers: from energy bands to dipolar excitons
• Evolution of flat bands in MoSe${}_2$/WSe${}_2$ moiré lattices: A study combining machine learning and band unfolding methods
• Electrons surf phason waves in moiré bilayers
• Ferromagnetic semimetal and charge-density wave phases of interacting electrons in a honeycomb moiré potential
• Localized Interlayer Excitons in MoSe2-WSe2 Heterostructures without a Moiré Potential