The Preparation and Identification of Rhombohedral Graphene for the Exploration of Strongly Correlated Phenomena

Graphene is a single layer of carbon atoms arranged in a hexagonal lattice. Multilayer graphene can form different stacking orders, which are defined by the orientation of the sublattice sites between adjacent layers. The Rhombohedral (ABC) stacking order has garnered a great deal of recent interest in the physics community. When aligned with hexagonal Boron Nitride (h-BN) rhombohedral graphene hosts a variety of emergent phenomena, including superconductivity and fractional Chern insulators. A major limitation in studying this system is caused by the ABC stacking order being metastable and occurring in nature less frequently than the stable Bernal (ABA) stacking order. The fabrication of rhombohedral graphene devices requires both quick identification and preservation of this stacking order, which are the objectives of this project. We utilize Scanning Kelvin Probe Microscopy (SKPM), to identify different stacking domains, exploiting the differing work functions of ABC and ABA stackings. Domains found via SKPM were confirmed using Raman spectroscopy technique. We present results from SKPM measurements and subsequent dry transfer towards the fabrication of dual-gated rhombohedral graphene devices.