Theory of resonant tunneling in bilayer-graphene/hexagonal-boron-nitride heterostructures

A theory is developed for calculating vertical tunneling current between two sheets of bilayer grapheneseparated by a thin, insulating layer of hexagonal boron nitride, neglecting many-body effects. Results are presented using physical parameters that enable comparison of the theory with recently reported experimental results. Observed resonant tunneling and negative differential resistance in the current–voltage characteristics are explained in terms of the electrostatically-induced band gap, gate voltage modulation, density of states near the band edge, and resonances with the upper sub-band. These observations are compared to ones from similar heterostructures formed with monolayer graphene.