Studying correlations and topology in multilayer rhombohedral graphene

In graphite’s metastable rhombohedral stacking configuration, the successive carbon sheets are shifted relative to each other in such a way that creates flat electronic bands with concentrated Berry curvature. These flat bands have been shown to be a hotbed for novel electronic orderings including integer and fractional quantum anomalous Hall states, moiré-driven topological electronic crystals, and superconductivity with apparent time-reversal symmetry breaking. These states are highly sensitive to sample parameters including the number of rhombohedral-stacked graphene layers, the relative twist angle of the multilayer graphene flake with one or both hBN dielectrics, and other possible factors including strain and proximity-induced spin-orbit coupling. The properties of multilayer rhombohedral graphene thus exhibit a range of sample-to-sample variations, and in many cases are not yet well understood. In this talk I will present some of our preliminary results towards a systematic study of multilayer rhombohedral graphene, focused on obtaining a comprehensive understanding of the rich phase space of this fascinating system.