三维光晶格中玻色凝聚气体基态波函数及干涉演化

基于Gross-Pitaevskii方程，运用有效化学势概念，研究了囚禁在组合势(由磁阱和三维光 晶格组成)中玻色凝聚气体在三维光晶格中的分布规律，并由此得到玻色凝聚气体的归 一化基态波函数.在取消组合势和仅取消光晶格而保留磁阱的两种情况下，运用传播子方 法求解出玻色凝聚气体密度分布的解析表达式.取消组合势后，理论计算所得到的玻色凝聚 气体聚随时间的演化规律与Greiner等的实验结果相一致.仅取消光晶格而保留磁阱时，研 究表明玻色凝聚气体的干涉模式呈现周期性的振荡行为.此外，在磁阱为各向异性的情况下 ，关键词：玻色凝聚气体磁阱光晶格干涉模式

The groud-state wave function and evolution of the interference pattern for a Bose-condensed gas in 3D optical lattices

Based on the Gross_Pitaevskii equation and by using the effective chemical potential,we study the distribution of the Bose_condensed gas in the combined potentials (magnetic trap and three_dimensional optical lattices).The normalized ground_state wave function is given from the distribution of the Bose_condensed gas.The analytical expression of the density distribution of the Bose_condensed gas is given by using the propagator method when the combined potentials and only the optical lattices are switched off,respectively.When the combined potentials are switched off,the theoretical results of this work agree well with the experiment by Greiner et al .When only the optical lattices are switched off,it is shown that the interference pattern will oscillate in the magnetic trap.In addition,the evolution of the interference pattern is also investigated in the case of anisotropic magnetic trap.