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利用密度重整化群研究了在粒子数小于半填充时一维光学晶格中费米子气体的超流特性.研究发现当格点总数N<22,排斥相互作用强度大于临界值时,粒子的束缚态会对应着费米系统在势阱中心产生的Mott绝缘态,边缘则为超流态.而当格点总数增大时,上述结论会有所不同.增强排斥相互作用首先出现的负的两粒子束缚能只能说明系统此时处于超流态,但是并没有相应的Mott绝缘态,只有当排斥作用足够强时才会有Mott绝缘态的出现,上述讨论进一步改善了文献[5]的结论.
The density regularization group was used to study the superfluidity of fermion gas in a one-dimensional optical lattice when the number of particles is less than half-filled. The results show that when the total number of lattice points is N <22 and the intensity of repulsive interaction is larger than the critical value, The bound state corresponds to the Mott insulation state in the center of the well due to the Fermi system, and the edge is in the superfluid state, whereas the above conclusion will be different when the total number of lattice points is increased. The two-particle binding energy only shows that the system is in a superfluid state at this time, but does not have the corresponding Mott insulation state. The Mott insulation state appears only when the repulsion is strong enough. The above discussion further improves the in conclusion.