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arXiv · 0810.2958

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

Krzysztof Byczuk·Walter Hofstetter·Dieter Vollhardt
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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.

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Krzysztof Byczuk, Walter Hofstetter, Dieter Vollhardt. 2008-10-16. Competition between Anderson localization and antiferromagnetism in correlated lattice fermion systems with disorder. https://doi.org/10.1103/physrevlett.102.146403

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