We theoretically and experimentally characterize the performance of the pairwise correlations from triple quantum correlated beams based on the cascaded four-wave mixing (FWM) processes.The pairwise correlations between any two of the beams are theoretically calculated and experimentally measured. The experimental and theoretical results are in good agreement. We find that two of the three pairwise correlations can be in the quantum regime. The other pairwise correlation is always in the classical regime. In addition, we also measure the triple-beam correlation which is always in the quantum regime. Such unbalanced and controllable pairwise correlation structures may be taken as advantages in practical quantum communications, for example, hierarchical quantum secret sharing. Our results also open the way for the classification and application of quantum states generated from the cascaded FWM processes.
图1 用于生成和探测量子关联的实验布局
图2 成对相关光的关联随系统增益的变化。(a) Pr2和C2之间关联的理论预测和实验结果。 (b) Pr2和C1之间关联的理论预测和实验结果。 (c) C2和C1之间关联的理论预测和实验结果
