▎ 摘 要
The density of states and conductivity are calculated for scatterers with nonzero range in monolayer graphene within a self-consistent Born approximation. For scatterers with a Gaussian potential, the minimum conductivity at the Dirac point 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 conductivity increases in proportion to the electron concentration in agreement with experiments and the minimum conductivity becomes about twice as large as the universal value.