▎ 摘　　要

We have done a study of graphene/hexagonal boron nitride (h-BN) thin films within the framework of density functional theory, and find that the interlayer interaction energy of a graphene/h-BN monolayer thin film is inversely proportional to the layer number. This analysis based on a method which simulates the interlayer interactions in lattice-mismatched thin films shows that thin films with four or more layers can have stable lattice-matched stacking geometries. We find that the maximum value of the band gap of the lattice-matched thin films having the same layer number, but different stacking sequences, decreases with respect to the layer number, even though one can consider several different stable stacking sequences of these feasible lattice-matched thin films. In addition, the band gap can be tuned by using an external electric field. We also propose six-layer graphene/h-BN bilayer thin films with 99-meV band gap or graphenelike linear dispersion depending on the stacking sequences.