arXiv:1012.3248 · Optics Letters
Absolute calibration of photodetectors: photocurrent multiplication versus photocurrent subtraction
I. N. Agafonov, Maria V. Chekhova, T. Sh. Iskhakov, Alexander N. Penin, Georgy O. Rytikov, O. A. Shcherbina
Abstract
We report testing of the new absolute method of photodetector calibration based on the difference-signal measurement for two-mode squeezed vacuum by comparison with the traditional absolute method based on coincidence counting. Using low-gain parametric downconversion, we have measured the quantum efficiency of a counting detector by both methods. The difference-signal method was adapted for the counting detectors by taking into account the dead-time effect.