Bilayer Graphene with Long-Range Scatterers Studied in a Self-Consistent Born Approximation

The density of states and conductivity are calculated for scatterers with nonzero range in bilayer graphene within a self-consistent Born approximation. For scatterers with a Gaussian potential, the minimum conductivity at zero energy remains universal in the clean limit, but increases with disorder and becomes nonuniversal for long-range scatterers. For charged impurities, we use the Thomas-Fermi approximation for the screening effect. The minimum conductivity increases with impurity concentration but the dependence is not so considerable. When the excited conduction band starts to be populated by electrons, the conductivity increases due to the increase in the screening effect.