Competition between Anderson localization and antiferromagnetism in correlated lattice fermion systems with disorder

TL;DR

This study investigates how disorder and electron interactions influence magnetic phases in the disordered Hubbard model, revealing the competition between Anderson localization and antiferromagnetism, with implications for cold atom experiments.

Contribution

It provides a detailed phase diagram of the disordered Hubbard model using dynamical mean-field theory, highlighting the distinct responses of Slater and Heisenberg antiferromagnets to disorder.

Findings

Weak interactions stabilize paramagnetic and antiferromagnetic metallic phases.

Strong disorder induces Anderson localization, suppressing antiferromagnetic order.

Slater and Heisenberg antiferromagnets respond differently to disorder.

Abstract

The magnetic ground state phase diagram of the disordered Hubbard model at half-filling is computed in dynamical mean-field theory supplemented with the spin resolved, typical local density of states. The competition between many-body correlations and disorder is found to stabilize paramagnetic and antiferromagnetic metallic phases at weak interactions. Strong disorder leads to Anderson localization of the electrons and suppresses the antiferromagnetic long-range order. Slater and Heisenberg antiferromagnets respond characteristically different to disorder. The results can be tested with cold fermionic atoms loaded into optical lattices.