连续变量量子纠缠态是量子信息研究中的一项重要的量子资源。实验上, 通常使用非简并光学参量振荡器(NOPO)制备具有正交振幅和正交位相分量量子关联的量子纠缠态光场。本文详细分析了注入泵浦场噪声以及注入信号场和闲置场噪声对NOPO输出场纠缠特性的影响。结果表明, 通过优化实验参数, 可以减小NOPO注入场的噪声对NOPO输出纠缠光场的影响。同时, 减小注入场的噪声, 选取位相压缩的泵浦场、噪声关联的信号场和闲置场作为注入信号, 可以进一步提高NOPO输出光场的纠缠程度。计算中选取的参数, 以实验为依据, 可以为实验中改善NOPO输出场的纠缠特性提供参考。

Continuous variable entangled state of light is an important resource in quantum information research.Experimentally, continuous variable entangled state of light with quantum correlation in quadrature amplitude and quadrature phase is usually generated by non-degenerate optical parametric oscillators(NOPO).The influence of noise from pump field, signal field and idle field on the entanglement characteristics of the output field from NOPO has been studied in detail.The result shows that, by optimizing the experimental parameters, the effect of the noise from injection fields of NOPO can be reduced, which influences the output entanglement fields of NOPO.Meanwhile, reduction of noise from injected field such as selecting phase squeezing pump field, noise correlating signal and idle field as injection signal, can further increase the entanglement of NOPO output field.Selected parameters in calculation are based on experiment, which can provide reference for improvement of the NOPO output entanglement characteristic in experiment.