Theory of Electron Scattering by Lattice Defects in Monolayer Graphene

Electron scattering by defects consisting of several strong and short-range impurities at A and B sublattice points lying close to each other is studied within a k.p scheme in monolayer graphene. In a defect consisting of a single impurity, a quasi-bound state like donor or acceptor state emerges near the Dirac point when the potential becomes extremely strong. In the case of AB pair impurities, the quasi-bound state splits into two and the resonance appears near the Dirac point for small scattering potential. In the case of defects consisting of many atoms, the number of resonances is given by that of AB pairs.