A systematic study was made of electron back-scattering phenomena during conduction for graphene nanoribbons with single-vacancy scatterers and dimensions within the capabilities of modern lithographic techniques. The analysis built upon an ab initio parameterized semi-empirical model that broke electron-hole symmetry and non-equilibrium Green’s-function methods for the calculation of the conductance distribution g. The underlying mechanism was based upon wave-function localizations and perturbations that in the case of the first π−π∗ plateau could give rise to impurity-like pseudo-gaps with both donor and acceptor characteristics. Confinement and geometry were crucial for the manifestation of such effects. Self-consistent quantum transport calculations characterize vacancies as local charging centers that could induce electrostatic inhomogeneities on the ribbon topology.

Effects Due to Backscattering and Pseudogap Features in Graphene Nanoribbons with Single Vacancies. I.Deretzis, G.Fiori, G.Iannaccone, A.La Magna: Physical Review B, 2010, 81[8], 085427