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Commensurate Two-Component Bosons in Optical Lattice: Groundstate Phase Diagram

Anatoly Kuklov·Nikolay Prokof'ev·Boris Svistunov
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Abstract

Two sorts of bosons in an optical lattice at commensurate filling factors can form five stable superfluid and insulating groundstates with rich and non-trivial phase diagram. The structure of the groundstate diagram is established by mapping $d$-dimensional quantum system onto a $(d+1)$-dimensional classical loop-current model and Monte Carlo simulations of the latter. Surprisingly, the quantum phase diagram features, besides second-order lines, a first-order transition and two multi-critical points. We explain why first-order transitions are generic for models with paring interactions using microscopic and mean-field arguments.

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Anatoly Kuklov, Nikolay Prokof'ev, Boris Svistunov. 2003-12-11. Commensurate Two-Component Bosons in Optical Lattice: Groundstate Phase Diagram. https://doi.org/10.1103/physrevlett.92.050402

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