耦合量子比特在最大纠缠混合态下几何量子失协鲁棒性的研究  

Robustness investigation on geometric quantum discord of coupled qubits initially in maximally entangled mixed states

作　　者：胡燕[1] 于雁霞[1] 嵇英华[1,2] 

机构地区：[1]江西师范大学物理与通信电子学院,江西南昌330022 [2]江西省光电子与通信重点实验室,江西南昌330022

出　　处：《量子电子学报》2013年第5期572-578,共7页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金(11164009)资助项目

摘　　要：几何测量量子失协是量子关联的一种表达形式。结合利用量子纠缠和几何量子失协,运用解析和数值模拟的方法,对非马尔科夫过程中耦合量子比特系统的量子关联动力学特性进行了比较研究。研究结果表明,在一定的初始态下,由于环境耗散作用的存在,量子纠缠和几何量子失协都随时间做递减的动力学演化,但几何量子失协比量子纠缠的递减要慢一些。表明几何量子失协的生存时间长于量子纠缠,更能抵抗环境的耗散作用、鲁棒性更好。因此,量子关联也是实现量子信息处理的有用资源。Geometric quantum discord is a measure of quantum correlations. Combining quantum entan~ glement and geometric quantum discord, the comparison of quantum correlations of two-qubits initially in X-state was investigated in nomMarkovian process by using analytical and numerical methods. The results show that in some initial states, both the concurrence and geometric quantum discord decay because of existence of the dissipation environments. However, the geometric quantum discord damps more slowly than concurrence does, which shows that the survival time of geometric quantum discord is longer than that of the entanglement. In other words, geometric quantum discord is more robust than entanglement to against the relaxation processes. Therefore, the quantum correlation is also a useful resource to realize quantum information processing.

关 键 词：量子关联 共生纠缠度 几何量子失协 耦合量子比特 

分 类 号：O431.2[机械工程—光学工程]