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Quantum phase transition of condensed bosons in optical lattices

Jun-Jun Liang·J. -Q. Liang·W. -M. Liu
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Abstract

In this paper we study the superfluid-Mott-insulator phase transition of ultracold dilute gas of bosonic atoms in an optical lattice by means of Green function method and Bogliubov transformation as well. The superfluid- Mott-insulator phase transition condition is determined by the energy-band structure with an obvious interpretation of the transition mechanism. Moreover the superfluid phase is explained explicitly from the energy spectrum derived in terms of Bogliubov approach.

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Jun-Jun Liang, J. -Q. Liang, W. -M. Liu. 2004-03-23. Quantum phase transition of condensed bosons in optical lattices. https://doi.org/10.1103/physreva.68.043605

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