Anderson localization vs. Mott-Hubbard metal-insulator transition in disordered, interacting lattice fermion systems

TL;DR

This paper reviews how Dynamical Mean-Field Theory (DMFT) can describe the interplay of Anderson localization and Mott insulator phases in disordered, interacting lattice fermion systems, revealing a new disorder-stabilized antiferromagnetic metal.

Contribution

It demonstrates that DMFT combined with geometric averaging effectively captures both Anderson localization and Mott insulating phases in disordered fermion systems, including novel phases.

Findings

DMFT with geometric averaging captures localization and Mott phases

Discovery of a disorder-stabilized antiferromagnetic metal

Phase diagram of the Anderson-Hubbard model at half filling

Abstract

We review recent progress in our theoretical understanding of strongly correlated fermion systems in the presence of disorder. Results were obtained by the application of a powerful nonperturbative approach, the Dynamical Mean-Field Theory (DMFT), to interacting disordered lattice fermions. In particular, we demonstrate that DMFT combined with geometric averaging over disorder can capture Anderson localization and Mott insulating phases on the level of one-particle correlation functions. Results are presented for the ground-state phase diagram of the Anderson-Hubbard model at half filling, both in the paramagnetic phase and in the presence of antiferromagnetic order. We find a new antiferromagnetic metal which is stabilized by disorder. Possible realizations of these quantum phases with ultracold fermions in optical lattices are discussed.