Commensurate Two-Component Bosons in an Optical Lattice: Ground State Phase Diagram
This is the pre-published version harvested from ArXiv. The published version is located at http://prl.aps.org/abstract/PRL/v92/i5/e050402
Two sorts of bosons in an optical lattice at commensurate filling factors can form five stable superfluid and insulating ground states with rich and nontrivial phase diagram. The structure of the ground state diagram is established by mapping a d-dimensional quantum system onto a (d+1)-dimensional classical loop-current model and Monte Carlo (MC) simulations of the latter. Surprisingly, the quantum phase diagram features, besides second-order lines, first-order transitions and two multicritical points. We explain why first-order transitions are generic for models with pairing interactions using microscopic and mean-field (MF) arguments. In some cases, the MC results strongly deviate from the MF predictions.
A Kuklov, N Prokof'ev, and B Svistunov. "Commensurate Two-Component Bosons in an Optical Lattice: Ground State Phase Diagram" Commensurate Two-Component Bosons in an Optical Lattice: Ground State Phase Diagram 92.5 (2004).
Available at: http://works.bepress.com/boris_svistunov/14