Scaling properties of diffusive electronic transport in graphene nanoribbons functionalized with methyl-groups

Abstract

We present a systematic study of the electronic transport properties of graphene nanoribbons functionalized with methyl-groups. Our numerical simulations are based on the Green’s function approach and the tight-binding description of graphene. In the case of a single adsorbate, the results are found to depend on the ribbon edge geometry and on the position of the impurity along the ribbon section. For random distribution of methyl-groups with increasing density, the transport regime passes from ballistic to diffusive and finally to localized, with the opening of a transport gap. In the diffusive regime, the electron mean free path turns out to be inversely proportional to the adsorbate density and, number of active conductive modes remained constant, inversely proportional to the ribbon width. The inferred scaling law for the transmission coefficient allows us to generalize the results to ribbons with different methyl-group densities, widths and lengths.