Abstract
We study the nature of the ground state of the two-dimensional extended boson Hubbard model on a square lattice by quantum Monte Carlo methods. We demonstrate that strong but finite on-site interaction along with a comparable nearest-neighbor repulsion result in a thermodynamically stable supersolid ground state for densities larger than , in contrast to fillings less than or for very large , where the checkerboard supersolid is unstable towards phase separation. We discuss the relevance of our results to realizations of supersolids using cold bosonic atoms in optical lattices.
- Received 15 December 2004
DOI:https://doi.org/10.1103/PhysRevLett.94.207202
©2005 American Physical Society