Absolute quantum efficiency calibration of analog detectors with twin photon current

Correlated photon is exploited as a tool for absolute quantum efficiency calibration of photon detectors working in the photon-counting regime. We extend the method from photon-counting regime to the absolute calibration of analog regime photon detectors. A revised calibration module is proposed based on balance detection and fluctuation restrictions conditions applied to analog photon detectors. An absolute calibration experimental system is established. This method shows a relative standard uncertainty of 2.1% and a relative deviation of 1% compared with those of the typical photomultiplier quantum efficiency.