Moiré patterns in graphene -- rhenium disulfide vertical heterostructures

Abstract

Vertical stacking of atomically thin materials offers a large platform for realizing novel properties enabled by proximity effects and moiré patterns. Here we focus on mechanically assembled heterostructures of graphene and ReS${}_2$, a van der Waals layered semiconductor. Using scanning tunneling microscopy and spectroscopy (STM/STS) we image the sharp edge between the two materials as well as areas of overlap. Locally resolved topographic images revealed the presence of a striped superpattern originating in the interlayer interactions between graphene's hexagonal structure and the triclinic, low in-plane symmetry of ReS${}_2$. We compare the results with a theoretical model that estimates the shape and angle dependence of the moiré pattern between graphene and ReS${}_2$. These results shed light on the complex interface phenomena between van der Waals materials with different lattice symmetries.

8 pages, 4 figures