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Metal-insulator transition in Hubbard-like models with random hopping

Matthew S. Foster·Andreas W. W. Ludwig
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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.

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Matthew S. Foster, Andreas W. W. Ludwig. 2007-02-09. Metal-insulator transition in Hubbard-like models with random hopping. https://doi.org/10.1103/physrevb.74.241102

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