量子点系统中纠缠的演化  

The evolution of entanglement in quantum dot system

作　　者：李季[1] 惠小强[1] 

机构地区：[1]西安邮电学院理学院,陕西西安710121

出　　处：《西安邮电学院学报》2011年第2期54-58,共5页Journal of Xi'an Institute of Posts and Telecommunications

基　　金：陕西省自然科学青年基金重点资助项目(2009JQ8006)

摘　　要：在多个量子点组成的自旋链系统中,各点之间的距离都很短,次近邻相互作用在很多情况下不能被忽略。研究有次近邻相互作用时,由四个量子点组成的自旋链系统中的边界纠缠情况,给出Concurrence的解析表达式及其随时间的演化情况。研究结果表明,次近邻相互作用对纠缠有着重要的影响,可以通过调节环境参数和近邻相互作用的强度来减小次近邻相互作用对系统纠缠的影响。这种调节方法在量子点系统中很容易实现。In multiple quantum dots spin chain,the distance between each dot is so short that the next nearest neighbor interaction can not be ignored in general.The boundary entanglement in four-qubit spin chain that composed by quantum dot system with the next nearest neighbor interaction is studied here,and the analytical expressions of Concurrence and its evolution are stressed.Research results show that the next nearest neighbor interaction has a great negative effect on the entanglement,and this negative effect can be reduced by controlling the environmental parameters and the strength of the nearest neighbor interaction.This controlling method is easy to realize in quantum dot system.

关 键 词：量子点 对纠缠 海森堡链 

分 类 号：O413[理学—理论物理]