标题： 优化双光子分布测量的信噪比 显示英文标题

标题： Optimizing the signal-to-noise ratio of biphoton distribution measurements

摘要： 单光子敏感相机现在可以作为纠缠光子对的大量并行符合计数器使用。 这使得能够以比传统点探测器光栅扫描高数量级的维度和更快的采集速度测量双光子联合概率分布；然而到目前为止，还没有通用公式可用于优化数据收集。 在这里，我们分析了此类测量对计数率、探测器噪声特性和阈值水平的依赖性。 我们推导了双光子联合概率分布及其信噪比（SNR）的表达式，其有效性超出低计数范围，直至探测器饱和。 该分析给出了可在测量前指定的全局最优信噪比的操作参数。 我们在有效范围内与实验测量结果高度一致，并讨论了高阈值下与理论模型的差异。 这项工作实现了在高维联合希尔伯特空间中对双光子联合概率分布的优化测量。 显示英文摘要

摘要： Single-photon-sensitive cameras can now be used as massively parallel coincidence counters for entangled photon pairs. This enables measurement of biphoton joint probability distributions with orders-of-magnitude greater dimensionality and faster acquisition speeds than traditional raster scanning of point detectors; to date, however, there has been no general formula available to optimize data collection. Here we analyze the dependence of such measurements on count rate, detector noise properties, and threshold levels. We derive expressions for the biphoton joint probability distribution and its signal-to-noise ratio (SNR), valid beyond the low-count regime up to detector saturation. The analysis gives operating parameters for global optimum SNR that may be specified prior to measurement. We find excellent agreement with experimental measurements within the range of validity, and discuss discrepancies with the theoretical model for high thresholds. This work enables optimized measurement of the biphoton joint probability distribution in high-dimensional joint Hilbert spaces.