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The low-energy theory for the Bose-Hubbard model and the normal ground state of bosons

Igor F. Herbut
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Abstract

A bosonic realization of the SU(2) Lie algebra and of its vector representation is constructed, and an effective low-energy description of the Bose-Hubbard model in the form of anisotropic theory of quantum rotors is proposed and discussed. A possibility of a normal zero-temperature bosonic phase with neither crystalline nor superfluid order around the tip of the checkerboard-solid lobe at half-integer fillings is examined.

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Igor F. Herbut. 1999-06-09. The low-energy theory for the Bose-Hubbard model and the normal ground state of bosons. https://doi.org/10.1103/physrevb.60.14503

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