Abstract:

A Monte-Carlo-based simulated annealing process combined with ab initio calculations is employed to investigate electronic and structural properties of boron nitride (BN)-doped graphene, in a wide doping range. We find that, for a given BN doping concentration, the doping-induced band gap can vary over an order of magnitude depending on the placement of the B and N atoms. We propose an analytical tight-binding model that reproduces the dependence of the band gap on both the concentration and the morphology obtained in the ab initio calculations and provides an upper bound for the band gap at a given BN concentration. We also predict that the dependence of the band gap with applied tensile stress should be strong, nonmonotonic, and anisotropic, within the range of strain values attainable experimentally.