title: Effects of strong correlations on the disorder-induced zero-bias anomaly in the extended Anderson-Hubbard model.
abstract: We study the effect of strong correlations on the zero-bias anomaly (ZBA) in disordered interacting systems. We focus on the two-dimensional extended Anderson-Hubbard model (EAHM) on a square lattice. The EAHM has both on-site and nearest-neighbour interactions and randomly chosen site energies. We use a mean-field theory that incorporates strong correlations and treats the disorder potential exactly. We use a simplified atomic-limit approximation for the diagonal inelastic self-energy that becomes exact in the large-disorder limit, and the off-diagonal self-energy is treated within the Hartree-Fock approximation. The validity of these approximations is discussed in detail. We find that strong correlations have a significant effect on the ZBA at half-filling, and enhance the ZBA gap when the interaction is finite ranged.
authors.affiliation: Department of Physics, Beijing Normal University, Beijing 100875, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Song
authors.forename: S
authors.initials: S
authors.lastname: Bulut
authors.forename: R
authors.initials: R
authors.lastname: Wortis
authors.forename: W A
authors.initials: WA
authors.lastname: Atkinson