均匀磁场作用下海森伯XXZ模型的热纠缠  

Thermal Entanglement in the Heisenberg XXZ Model Under an Uniform Magnetic Field

作　　者：吴桂红[1] 陈涛[2] 

机构地区：[1]中南林业科技大学理学院,湖南株洲412006 [2]湖北师范学院物理系,湖北黄石435002

出　　处：《河北师范大学学报（自然科学版）》2006年第6期668-672,共5页Journal of Hebei Normal University：Natural Science

基　　金：中南林业科技大学新进高层次人才项目(101-0649)

摘　　要：分析了均匀磁场作用下2量子比特各向异性海森伯XXZ模型的热纠缠态,讨论了外加均匀磁场对XXZ模型的2种特殊情况即各向同性海森伯XY模型和各向同性海森伯XXZ模型的纠缠度的影响.对于一定的温度,耦合常数绝对值的增加能够增加纠缠度,但是纠缠度却随着温度的增加而减小,直到临界温度时纠缠度为0.当外加磁场强度大于一定值时,随着磁场强度的增加,纠缠度和临界温度相应增大.The thermal entanglement of a two-qubit Heisenberg XYZ model under a uniform external magnetic field is analyzed,and the influences for the concurrence of the isotropic XY and XXZ models which are special cases of the anisotropic Heisenberg XXZ model in terms of the uniform external magnetic are discussed. The increased absolute value of J can increase the concurrence for a given T, but the concurrence decreases with the increase of temperature and becomes zero until it reaches the critical temperature. When the uniform external magnetic is big enough and increases, the concurrence and the critical temperature increase.

关 键 词：各向异性海森伯XXZ模型 量子比特 热纠缠态 纠缠度 临界温度 

分 类 号：O413.1[理学—理论物理]