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arXiv · 0903.0845

Strong-coupling perturbation theory for the extended Bose-Hubbard model

M. Iskin·J. K. Freericks
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Abstract

We develop a strong-coupling perturbation theory for the extended Bose-Hubbard model with on-site and nearest-neighbor boson-boson repulsions on ($d > 1$)-dimensional hypercubic lattices. Analytical expressions for the ground-state phase boundaries between the incompressible (Mott or charge-density-wave insulators) and the compressible (superfluid or supersolid) phases are derived up to third order in the hopping $t$. We also briefly discuss possible implications of our results in the context of ultracold dipolar Bose gases with dipole-dipole interactions loaded into optical lattices.

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M. Iskin, J. K. Freericks. 2009-03-04. Strong-coupling perturbation theory for the extended Bose-Hubbard model. https://doi.org/10.1103/physreva.79.053634

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