Quantum phase transitions of ultra-cold Bose system in non-rectangular optical lattices
arXiv:1112.4161 · doi:10.1103/PhysRevA.85.023619
Abstract
In this paper, we investigate systematically the Mott-insulator-Superfluid quantum phase transitions for ultracold scalar bosons in triangular, hexagonal, as well as Kagomé optical lattices. With the help of field-theoretical effective potential, by treating the hopping term in Bose-Hubbard model as perturbation, we calculate the phase boundaries analytically for different integer filling factors. Our analytical results are in good agreement with recent numerical results.
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