Studying Transition Metal Dichalcogenide Superlattices with nano-ARPES

Two-dimensional layered materials, especially monolayer transition metal dichalcogenides, have demonstrated lasting impact as a platform for combining and tuning electronic and optical behaviors on the nanoscale. The realization that moiré superlattices in these systems provide tunable control over correlations has sparked renewed interest through analogy to the family of high-temperature superconductors and in light of new phenomena such as moiré excitons. As a complement to modeling, a bottom-up understanding of these phenomena and interlayer hybridization motivates direct measurements of the electronic structures of the host materials. Nano-ARPES enables these experiments on clean, mechanically-exfoliated heterostructures where the impact of substrate and superlattice interaction on the electrons can be fully explored. In this talk, I show how this technique can address basic questions of electronic and structural order in a few model systems: heterobilayer interfaces, and in the interface of TMD monolayers with a substrate. Among the rich phenomena present at the interface, we will focus especially on the presence or absence of hybridization effects in short and long wavelength superlattices.