2010/05/21 by Y. Nakano, Yuki Nakano, Nakano, Yuki +10
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Quantum Gases (cond-mat.quant-gas) #Strongly Correlated Electrons (cond-mat.str-el) #Theoretical and Computational Physics #cond-mat.quant-gas #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1005.3997
13 pages, 17 figures
arxiv created 2010/05/21 · openalex publication_date 2010/05/21 · arxiv updated 2010/05/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the three-dimensional bosonic t-J model, i.e., the t-J model of "bosonic electrons" at finite temperatures. This model describes a system of cold bosonic atoms with two species in an optical lattice. The model is derived from the Hubbard model for very large on-site repulsive interaction between bosons of same species (hard-core nature) and also strong correlations between different species. The operator Bxσ for an atom at the site x with a two-component (pseudo-) spin σ(=1,2) is treated as a hard-core boson operator, and represented by a composite of two slave particles; a spinon described by a CP1 field (Schwinger boson) zxσ and a holon described by a hard-core-boson field ϕx as Bxσ=ϕ^†x zxσ. ϕx is then expressed by a pseudo-spin, which is, in turn, represented by another CP1 (pseudo) spinon wxη as ϕx = wx2^†wx1. We then have a double-CP1 representation of the model by zxσ and wxη. By means of Monte Carlo simulations of this bosonic t-J model, we study its phase structure and the possible phenomena like appearance of antiferromagnetic long-range order, Bose-Einstein condensation, phase separation, etc. They should be compared with the possible experimental results of a recently studied boson-boson mixture like 87Rb and 41K in an optical lattice.