We calculate the density of states of interacting electrons in a tight-binding lattice with substitutional disorder. The random potential is not assumed to be small, and it is therefore treated in the coherent-potential approximation. We find that the anomalous behavior of the density of states near the Fermi energy ($\sim {|E-E_F|}^{\frac{1}{2}}$) is still described by the Altshuler-Aronov formula, although that formula was derived in the limit of a homogeneous electron gas with weak impurity scattering. The cancellation of band-structure and strong-scattering effects within our model is explicitly demonstrated. This provides strong evidence for the universality of the Altshuler-Aronov result in disordered metals.

• Received 17 April 1987

DOI:https://doi.org/10.1103/PhysRevB.36.2924