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arXiv · cond-mat/0412734

Zoo of quantum phases and excitations of cold bosonic atoms in optical lattices

Abstract

Quantum phases and phase transitions of weakly- to strongly-interacting bosonic atoms in deep to shallow optical lattices are described by a {\it single multi-orbital mean-field approach in real space}. For weakly-interacting bosons in 1D, the critical value of the superfluid to Mott insulator (MI) transition found is in excellent agreement with {\it many-body} treatments of the Bose-Hubbard model. For strongly-interacting bosons, (i) additional MI phases appear, for which two (or more) atoms residing in {\it each site} undergo a Tonks-Girardeau-like transition and localize and (ii) on-site excitation becomes the excitation lowest in energy. Experimental implications are discussed.

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Ofir E. Alon, Alexej I. Streltsov, Lorenz S. Cederbaum. 2004-12-28. Zoo of quantum phases and excitations of cold bosonic atoms in optical lattices. https://doi.org/10.1103/physrevlett.95.030405

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