基于关联方向测量的量子关联

Quantum correlation on the correlation directions measurements

通过讨论量子失协的上界,给出可达熵量子关联态的一个必要条件.对于双量子比特系统,利用可获得经典关联的最佳测量定义了关联方向上最小的量子失协,分析得到该度量是量子失协很好的逼近结果.最后,讨论量子关联的动力学过程,发现量子关联在衰减的过程中出现了突然的改变,利用关联方向上最小的量子失协给出了该现象的合理解释.

We discuss the upper bound of quantum discord, and derive a necessary condition for the reachable entropy quantum correlated states. We analyze the optimal measurements to access classical correlation in arbitrary two-qubit system. Then, we define the minimum quantum discord on the correlation direction, and demonstrate that it could be a good approximation of quantum discord. Finally, we study the dynamics of quantum correlation, which exhibits a sudden change under the decayed process, then we give a reasonable interpretation for this phenomenon with respects to the minimum quantum discord on the correlation direction.