Moir\'e patterns in graphene -- rhenium disulfide vertical heterostructures

TL;DR

This study investigates moiré patterns in graphene-ReS₂ heterostructures, revealing complex interface phenomena driven by lattice symmetry differences through experimental imaging and theoretical modeling.

Contribution

It provides the first detailed imaging and analysis of moiré patterns in graphene and ReS₂ heterostructures, highlighting the effects of lattice symmetry mismatch.

Findings

Identification of striped superpatterns at the interface

Correlation between moiré pattern shape and lattice orientation

Theoretical model explaining pattern dependence on angle

Abstract

Vertical stacking of atomically thin materials offers a large platform for realizing novel properties enabled by proximity effects and moir\'e 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 moir\'e pattern between graphene and ReS$_2$. These results shed light on the complex interface phenomena between van der Waals materials with different lattice symmetries.