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

几何测量量子失协是量子关联的一种表达形式。本文结合利用量子纠缠和几何量子失协，对非马尔科夫过程中的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。运用解析和数值模拟的方法，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、健壮性更好。因此，量子关联也是实现量子信息处理的有用资源。

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

Geometric quantum discord is a measure of quantum correlations. Combining quantum entanglement and geometric quantum discord, we investigate the comparison of quantum correlations of two-qubits initially in X-state in non-Markovian process. The results show, by using analytical and numerical methods, in some initial states, both the concurrence and the geometric quantum discord will decay because of the existence of the dissipation environments. However, the geometric quantum discord damps slowly than concurrence does, which shows the survival time of geometric quantum discord longer than 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.