The Hanbury Brown and Twiss (HBT) interferometer was proposed to observe intensity correlations of starlight to measure a star’s angular diameter. As the intensity of light that reaches the detector from a star is very weak, one cannot usually get a workable signal-to-noise ratio. We propose an improved HBT interferometric scheme incorporating optical parametric amplifiers (OPA) into the system to amplify the correlation signal. Remarkably, for weak star light, the signal-to-noise ratio (SNR) in the new HBT interferometric scheme is much better than that of conventional HBT interferometer. Our work is valuable in measuring a star whose intensity at the detector is low and maybe also applicable in remote sensing and long-distance quantum imaging where the light passed through the object is weak after a long distance transmission.

中文翻译：

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使用参量放大增强Hanbury Brown和Twiss干涉法

提出使用Hanbury Brown and Twiss（HBT）干涉仪来观察星光的强度相关性，以测量恒星的角直径。由于从恒星到达探测器的光强度非常弱，因此通常无法获得可行的信噪比。我们提出了一种改进的HBT干涉方案，该方案将光参量放大器（OPA）纳入系统中以放大相关信号。值得注意的是，对于微弱的星光，新的HBT干涉测量方案中的信噪比（SNR）比传统的HBT干涉仪好得多。我们的工作对于测量在检测器处强度较低的恒星非常有价值，并且可能还适用于遥感和长距离量子成像，其中长距离传输后穿过物体的光微弱。