Modified graphene with small BN domain: an effective method for band gap opening (1012.4934v1)

Abstract: BN domains are easy to form in the basal plane of graphene due to phase separation. With first-principles DFT calculations, it is demonstrated theoretically that the band gap of graphene can be opened effectively around K (or K') points by doping the small BN domains. It is also found that the random doping with B or N is possible to open a small gap in the Dirac points, except for the modulation of Fermi level. The surface charge which belongs to the $\pi$ states near Dirac points is found to be redistributed locally. The charge redistribution is contributed to the change of localized potential due to the doping effects. This may be the reason that the energy states near Dirac points is just disturbed in the energy region [-0.4eV, 0.4eV] for the doping of BN domain. Thus, we suggest that the band opening induced by the doped BN domain is due to the breaking of localized symmetry of the potential. Doping graphene with BN domains is an effective method to open a band gap with quasi-linear dissipation near Dirac point.