具有Dzyaloshinskii-Moriya相互作用的一维随机量子XY模型中的纠缠特性  

The entanglement in one-dimensional random XY spin chain with Dzyaloshinskii-Moriya interaction

作　　者：单传家[1] 程维文[1] 刘堂昆[1] 黄燕霞[1] 李宏[1] 

机构地区：[1]湖北师范学院物理系,黄石435002

出　　处：《物理学报》2008年第5期2687-2694,共8页Acta Physica Sinica

基　　金：湖北省科技研究重大项目(批准号:Z200522001);湖北省自然科学基金(批准号:2006ABA055);湖北师范学院研究生启动项目(批准号:2007D20)资助的课题~~

摘　　要：研究了一维随机量子XY自旋链中中心两量子位的纠缠特性,在该系统中引入了自旋间的交换耦合杂质、磁杂质和Dzyaloshinskii-Moriya相互作用,并且杂质满足高斯分布关系.通过数值计算,求出了自旋的关联函数和平均磁化强度,给出了Concurrence的解析表达式.结果表明:高斯分布和Dzyaloshinskii-Moriya相互作用对两量子位的纠缠有重要的影响,选择合适的交换耦合、外界磁场和Dzyaloshinskii-Moriya相互作用参数,可以控制和提高中心两量子位的纠缠.In this paper, the entanglement in one-dimensional random XY spin system with Dzyaloshinskii-Moriya interaction is investigated, for which the impurities of exchange couplings and the external magnetic fields are considered as random Gaussian distribution variables. By solving the different spin-spin correlation functions and the average magnetization per spin, the concurrence is found. The results show that the Gaussian distribution and Dzyaloshinskii-Moriya interaction have considerable effect on the entanglement near particular locations of the system. Moreover, the entanglement can be controlled and enhanced by varying the distributions of the impurities, the strength of external magnetic field and Dzyaloshinskii-Moriya interaction.

关 键 词：纠缠 随机量子XY模型 高斯分布 Dzyaloshinskii-Moriya相互作用 

分 类 号：O413.1[理学—理论物理]