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arXiv:1205.6641 · International Journal of Modern Physics B

MOTT INSULATOR-SUPERFLUID TRANSITION IN A GENERALIZED BOSE–HUBBARD MODEL WITH TOPOLOGICALLY NONTRIVIAL FLAT-BAND

XING-HAI ZHANG, SU-PENG KOU

Published Dec 20, 2012• 1 citation
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Abstract

In this paper, we studied a generalized Bose–Hubbard model on a checkerboard lattice with topologically nontrivial flat-band. We used mean-field method to decouple the model Hamiltonian and obtained phase diagram by Landau theory of second-order phase transition. We further calculate the energy gap and the dispersion of quasi-particle or quasi-hole in Mott insulator phase and found that in strong interaction limit the quasi-particles or the quasi-holes also have flat-bands.

DOI
10.1142/s0217979212502141

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