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arXiv · 0709.0853

Quantum Phase Transitions and the Hidden Order in a Two-Chain Extended Boson Hubbard Model at Half-Odd-Integer Fillings

Yu-Wen Lee
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Abstract

We study the phase diagram of two weakly coupled one-dimensional dipolar boson chains at half-odd-integer fillings. We find that the system contains a rich phase diagram. Four different phases are found. They are the Mott insulators, the single-particle resonant superfluid, the paired superfluid, and the bond- or inter-chain density waves. Moreover, the Mott insulating phase can be further classified according to a hidden string order parameter, which is analogous to the one investigated recently in the one-dimensional boson Mott insulator at integer fillings.

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Yu-Wen Lee. 2007-09-17. Quantum Phase Transitions and the Hidden Order in a Two-Chain Extended Boson Hubbard Model at Half-Odd-Integer Fillings. https://doi.org/10.1103/physrevb.77.064514

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