Density-dependent tunneling in the extended Bose–Hubbard model

M Maik, P Hauke, O Dutta, M Lewenstein… - New Journal of …, 2013 - iopscience.iop.org
M Maik, P Hauke, O Dutta, M Lewenstein, J Zakrzewski
New Journal of Physics, 2013iopscience.iop.org
Recently, it has become apparent that when the interactions between polar molecules in
optical lattices become strong, the conventional description using the extended Hubbard
model has to be modified by additional terms, in particular a density-dependent tunneling
term. We investigate here the influence of this term on the ground-state phase diagrams of
the two-dimensional extended Bose–Hubbard model. Using quantum Monte Carlo
simulations, we investigate the changes of the superfluid, supersolid and phase-separated …
Abstract
Recently, it has become apparent that when the interactions between polar molecules in optical lattices become strong, the conventional description using the extended Hubbard model has to be modified by additional terms, in particular a density-dependent tunneling term. We investigate here the influence of this term on the ground-state phase diagrams of the two-dimensional extended Bose–Hubbard model. Using quantum Monte Carlo simulations, we investigate the changes of the superfluid, supersolid and phase-separated parameter regions in the phase diagram of the system. By studying the interplay of the density-dependent hopping with the usual on-site interaction U and nearest-neighbor repulsion V, we show that the ground-state phase diagrams differ significantly from those expected from the standard extended Bose–Hubbard model.
iopscience.iop.org