基于纠缠光子方法测量光电探测器量子效率的研究

Quantum-efficiency measurement of photodetectors based on entangled photons

光辐射传感器的定标是保证遥感数据精度及可利用价值的基础支撑技术。现行辐射定标方法都需要建立高精度初级标准及标准传递链,传递环节是误差的主要来源。纠缠光子理论为实现“无标准传递”的辐射定标开辟了崭新的技术途径。报道了在光子计数模式下利用非线性光学的非经典效应绝对定标光电探测器的新方法,测量是通过BBO非线性晶体的参量下转换形成的702 nm简并的纠缠光子方法来实现的。实验测得光电倍增管在该波长处的量子效率,结果显示有0.1%的偏差。该方法本身具有绝对性,不依赖于任何外部定标的辐射标准。

The calibration of radiometric sensors is critical to ensure the accuracy of the remote sensing data and their usability. The current methods of the radiometric calibration are based on the establishment of high-precision primary standard and standard transfer chain, and the transfer chain is the main source of errors. The entangled photons-based theory creates a new technical way to realize the radiometric calibration of ＂standardless transfer＂. The method of absolute calibration of photodetectors based on a nonclassical effect of the nonlinear optics in the photon-counting regime was discussed. The measurement was realized with the technique of entangled photons at 702 nm generated by a parametric down conversion process in a nonlinear crystal of BBO. The photomultiplier quantum-efficiency at the wavelength was measured during the experiment. It is estimated that the deviation is 0. 1%. The technique is independent of any externally calibrated radiometric standards.