Absolute calibration of Analog Detectors using Stimulated Parametric Down Conversion

TL;DR

This paper extends the use of stimulated parametric down conversion for the absolute calibration of analog photodetectors at higher photon fluxes, overcoming limitations of spontaneous down conversion methods.

Contribution

It introduces the use of stimulated parametric down conversion for calibrating analog detectors at higher photon fluxes, expanding the applicability of the technique.

Findings

Stimulated PDC enables calibration at higher photon fluxes.

The method overcomes intrinsic limitations of spontaneous PDC.

Preliminary uncertainty analysis is provided.

Abstract

Spontaneous parametric down conversion has been largely exploited as a tool for absolute calibration of photon counting detectors, photomultiplier tubes or avalanche photodiodes working in Geiger regime. In this work we investigate the extension of this technique from very low photon flux of photon counting regime to the absolute calibration of analog photodetectors at higher photon flux. Moving toward higher photon rate, i.e. at high gain regime, with the spontaneous parametric down conversion shows intrinsic limitations of the method, while the stimulated parametric down conversion process, where a seed beam properly injected into the crystal in order to increase the photon generation rate in the conjugate arm, allows us to work around this problem. A preliminary uncertainty budget is discussed.