针对量子光学实验的特殊要求,通过设计优化宽带低噪声放大电路,研制出宽带低噪声光电探测器。我们重点分析了影响光电探测器增益、带宽和噪声的因素,通过选择合适的光电二极管、取样电阻、反馈电阻和输出电容,获得了宽带低噪声光电探测器。该光电探测器的带宽为2~50 MHz,能够用于输入功率达15 mW光场的噪声测量,适用于包括平衡零拍探测、差拍探测等量子光学实验。考虑到在量子光学实验中需要一对平衡的光电探测器,我们制作了一对2 MHz~31 MHz带宽内共模抑制比大于30 dB的平衡光电探测器,并用于1064 nm激光和1550 nm激光的强度噪声测量和散粒噪声基准的校准。

We report a kind of low-noise,broadband photo-detector that can be applied in the quantum optics experiments.Based on the proper photo-diode,sampling resistor,feedback resistor and capacity were selected,a low-noise,broadband photo-detector was designed and fabricated.The photo-detector can be used to detect the quantum noise with the band-width of 2-50 MHz and the incident power of up to 15 mW.It can also be applied in the quantum optics experiments such as balance detectors,homodyne detectors and so on.A pair of identical photo-detectors with the band-width of 2-31 MHz and Common Mode Rejection Ratio of 30 dB was used as balance detectors to measure the intensity noise of white light,cw single frequency 1064 nm laser and 1550 nm laser.