用微扰法计算了光晶格中的玻色凝聚粒子从超流态到绝缘态相变的临界值,使用的方法与平均场理论不一样,但物理图像清楚,更容易理解,得到的结果与平均场理论一致。

In this paper, we calculated the critical value of Bose-condensed atoms for superfluid-to-insulator phase transition by using perturbation method, which was different with the method of mean-field approximation.But the perturbation method has gota clear physic picture, and easier to be understood.The results were same by using both methods.