Strong coupling study of spin-1 bosons in square and triangular optical lattices

22nd International Laser Physics Workshop

Kimura, Takashi^1

Department of Mathematics and Physics, Kanagawa University, 2946 Hiratsuka, Kanagawa 259-1293, Japan^1

关键词: Lattice geometry;    Nearest neighbors;    Square lattices;    Strong coupling;    Strong-coupling expansion;    Superfluid-Mott-insulator;    Transfer integral;    Triangular lattice;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/497/1/012024/pdf
DOI  :  10.1088/1742-6596/497/1/012024

来源: IOP

【 摘 要 】

We examine the superfluid-Mott insulator (SF-MI) transition of antiferromagnetically interacting spin-1 bosons trapped in a square or triangular optical lattice. We perform a strong-coupling expansion up to the third order in the transfer integral t between the nearest-neighbor lattices. As expected from previous studies, an MI phase with an even number of bosons is considerably more stable against the SF phase than it is with an odd number of bosons. Results for the triangular lattice are similar to those for the square lattice, which suggests that the lattice geometry does not strongly affect the stability of the MI phase against the SF phase.