Metal-insulator transition in Hubbard-like models with random hopping
arXiv:cond-mat/0607574 · doi:10.1103/PhysRevB.74.241102
Abstract
An instability of a diffusive Fermi liquid, indicative of a metal-insulator transition (expected to be of first order), arising solely from the competition between quenched disorder and short-ranged interparticle interactions is identified in Hubbard-like models for spinless fermions, subject to (complex) random hopping at half-filling on bipartite lattices. The instability, found within a Finkel'stein Non-Linear Sigma Model treatment in d = (2 + epsilon) > 2 dimensions, originates from an underlying particle-hole like (so-called "chiral") symmetry, shared by both disorder and interactions. In the clean, interacting Fermi liquid this symmetry is responsible for the (completely different) "nesting" instability.
5 pages, 1 figure. v2: Corrected simple algebraic error in Eq. (10b). The metal-insulator transition is now predicted to be first order. v3: References updated, published version