1997/11/20 by Christian Pich, C. Pich, Erwin Frey +1 · 2 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevb.57.13712
19 pages, ReVTeX, 18 figures included, submitted to PRB
arxiv created 1997/11/20 · openalex publication_date 1998/06/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We determine the zero-temperature phase diagram of the hard-core Bose-Hubbard model on a square lattice by mean-field theory supplemented by a linear spin-wave analysis. Due to the interplay between nearest- and next-nearest-neighbor interaction and cubic anisotropy several supersolid phases with checkerboard, stripe-domain, or intermediate symmetry are stabilized. The phase diagrams show three different topologies depending on the relative strength of nearest- and next-nearest-neighbor interaction. We also find a rich variety of new quantum critical behavior and multicritical points and discuss the corresponding effective actions and universality classes.