EFFECTS OF THE NEXT-NEAREST-NEIGHBOR HOPPING IN OPTICAL LATTICES

作者：Yune Gao, Fuxiang Han · 发表于：Modern Physics Letters B · 年份：2008 · DOI：10.1142/s0217984908014572 · 被引用次数：5 · 研究领域：Cold Atom Physics and Bose-Einstein Condensates、Physics of Superconductivity and Magnetism、Spectroscopy and Laser Applications

Introducing the next-nearest-neighbor hopping t′ into the Bose–Hubbard model, we study its effects on the phase diagram, on the ground-state energy, and on the quasiparticle and quasihole dispersion relations of the Mott insulating phase in optical lattices. We have found that a negative value of t′ enlarges the Mott-insulating region on the phase diagram, while a positive value of t′ acts oppositely. We have also found that the effects of t′ are dependent on the dimensionality of optical lattices with its effects largest in three-dimensional optical lattices.