Electronic Properties of Graphene/h-BN Bilayer Superlattices

We study the electronic properties of superlattices composed of a graphene and hexagonal boron nitride (h-BN) bilayer in the framework of density functional theory. Depending on the stacking sequences of superlattices, various interesting electronic properties are observed. The stable superlattice with the shortest stacking period is found to be a narrow-gap semiconductor with a very small effective mass. On the other hand, almost linear dispersion relations should appear around the K point in a stable superlattice with a longer stacking period. These almost linear bands are found to split owing to weak but finite inter-graphene interactions mediated by h-BN bilayers.