论文标题
使用多光子发射诊断参数下调的关节相关性
Diagnosing phase correlations in the joint spectrum of parametric downconversion using multi-photon emission
论文作者
论文摘要
新量子光源的开发需要表征其关节光谱特性的强大而方便的方法。测量光子对之间的关节光谱强度忽略了光谱相的任何相关性，这可能导致降低量子干扰的质量。完全相敏感的表征倾向于需要更大的实验复杂性。在这里，我们研究了频率分辨的双对发射对光谱相相关的敏感性，特别是对于存在简单形式的相关相的存在，该相位可以由the的泵浦泵激光脉冲产生。我们观察到四个光子重合的干扰条纹，这取决于所有四个光子的频率，其时期取决于它们相关的强度。我们还表明，即使未检测到相应的惰轮光子，JSA中的相位相关诱导两个信号光子之间的光谱强度相关性，并将此相关模式与单个信号光子的纯度联系起来。这些效果将在评估量子技术的新光子对来源中很有用，尤其是因为与关节光谱强度测量相比，我们几乎不需要额外的复杂性 - 本质上只是检测每个输出端口中至少两个光子的能力。
The development of new quantum light sources requires robust and convenient methods of characterizing their joint spectral properties. Measuring the joint spectral intensity between a photon pair ignores any correlations in spectral phase which may be responsible for degrading the quality of quantum interference. A fully phase-sensitive characterization tends to require significantly more experimental complexity. Here, we investigate the sensitivity of the frequency-resolved double-pair emission to spectral phase correlations, in particular to the presence of a simple form of correlated phase which can be generated by a chirped pump laser pulse. We observe interference fringes in the four photon coincidences which depend on the frequencies of all four photons, with a period which depends on the strength of their correlation. We also show that phase correlations in the JSA induce spectral intensity correlations between two signal photons, even when the corresponding idler photons are not detected, and link this correlation pattern to the purity of a single signal photon. These effects will be useful in assessing new photon-pair sources for quantum technologies, especially since we require little additional complexity compared to a joint spectral intensity measurement - essentially just the ability to detect at least two photons in each output port.
