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arXiv · 1305.6072

Disorder-induced Localization in a Strongly Correlated Atomic Hubbard Gas

Abstract

We observe the emergence of a disorder-induced insulating state in a strongly interacting atomic Fermi gas trapped in an optical lattice. This closed quantum system free of a thermal reservoir realizes the disordered Fermi-Hubbard model, which is a minimal model for strongly correlated electronic solids. In measurements of disorder-induced localization obtained via mass transport, we detect interaction-driven delocalization and localization that persists as the temperature of the gas is raised. These behaviors are consistent with many-body localization, which is a novel paradigm for understanding localization in interacting quantum systems at non-zero temperature.

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S. S. Kondov, W. R. McGehee, W. Xu, B. DeMarco. 2014-10-03. Disorder-induced Localization in a Strongly Correlated Atomic Hubbard Gas. https://doi.org/10.1103/physrevlett.114.083002

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