2-qubit系统的纠缠鲁棒性

Robustness of two-qubit system under the depolarization noise

研究了2-qubit量子系统在退极化噪声作用下的一些纠缠特性.通过对ansatz态纠缠演化的分析,给出了纠缠和纠缠鲁棒性的解析关系.此外纠缠猝死时间在很大程度上取决于量子态的纠缠和鲁棒性.对于纯态,纠缠鲁棒性完全取决于纠缠;但是混态将会复杂许多,其鲁棒性除了受自身纠缠的影响以外,还会受到其他纠缠度的影响.

Some entanglement properties of two-qubit system under the depolarization noise were in- vestigated.By analyzing the evolution of entanglement for the ansatz states,the analytical expression be- tween entanglement and entanglement robustness was obtained.In addition,the time of entanglement sud- den death（ESD）depended largely on the entanglement and entanglement robustness.It could be found that entanglement robustness of two-qubit system,for an arbitrary pure state,completely depended on its entanglement.However,this was not always true in mixed system.The robustness of mixed state was in- fluenced by its own entanglement,but also by other effects of entanglement.