用量子相位算符计算了凝聚体相位的具体表达式, 发现凝聚体的相位与时间,初始相位,非相互作用能和粒子数有关。然后进一步计算了具有相互作用的两凝聚体的相对相位,给出了凝聚体的相干条件。最后,在TF近似下,对于谐振势中的一定原子数, 发现原子阱基本上决定了凝聚体的相位, 它相当于光激光中谐振腔的作用。

Using the phase operator, the expression of the phase of Bose-Einstein condensate is obtained, which associates with time, initial phase, non-interaction energy and the atom number. Further, the interference condition of two condensates is given after calculating the relative phase of two condensates with interaction. Finally, it is found that the phase of condensate is mainly determined by the potential well for a finite atom number with the TF approximation, which is similar to the cavity of optical laser.