非均匀磁场作用下的混合海森堡XXZ自旋模型的时间演化  

Time Evolution of Entanglement for Mixed-spin Heisenberg XXZ Model under Nonuniform External Magnetic Field

作　　者：杨希 冉扬强[2] 

机构地区：[1]重庆市清华中学,巴南区重庆400054 [2]西南大学物理科学与技术学院,北碚区重庆400715

出　　处：《量子光学学报》2015年第4期298-306,共9页Journal of Quantum Optics

基　　金：国家自然科学基金(10875087)

摘　　要：研究了在非均匀磁场作用下的海森堡XXZ自旋模型的时间演化情况。首先对纠缠度的定义进行了合理推广并证明,将其应用于混合自旋模型中。然后通过对哈密顿量的求解,找到了不同初态下系统随时间演化的密度矩阵。再进行数值计算,从而得到系统的纠缠度,分析了纠缠度随时间的变化情况,讨论了各个参数以及系统初始状态对纠缠度的影响。The time evolution of entanglement for Heisenberg XXZ model under nonuniform external magnetic field was studied.Firstly,the definition of concurrence was extended reasonably.The time evolution operator was obtained by calculating the Hamilton of this model.And the different initial states were selected,and the density matrix of this system was obtained as well,then the concurrence could be calculated easily.Finally,the concurrence of this model was analyzed with time,and various parameters on the degree of entanglement and the different initial states were discussed as well.

关 键 词：海森堡XXZ模型 纠缠度 时间演化 

分 类 号：O431[机械工程—光学工程]