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arXiv · 1607.07708

Multitude of phases in correlated lattice fermion systems with spin-dependent disorder

J. Skolimowski·D. Vollhardt·K. Byczuk
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Abstract

The magnetic phases induced by the interplay between disorder acting only on particles with a given spin projection ("spin-dependent disorder") and a local repulsive interaction is explored. To this end the magnetic ground state phase diagram of the Hubbard model at half-filling is computed within dynamical mean-field theory combined with the geometric average over disorder, which is able to describe Anderson localization. Five distinct phases are identified: a ferromagnetically polarized metal, two types of insulators, and two types of spin-selective localized phases. The latter four phases possess different long-range order of the spins. The predicted phase diagram may be tested experimentally using cold fermions in optical lattices subject to spin-dependent random potentials.

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J. Skolimowski, D. Vollhardt, K. Byczuk. 2016-07-26. Multitude of phases in correlated lattice fermion systems with spin-dependent disorder. https://doi.org/10.1088/1361-648x/aae6b6

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