Influence of pump fluctuations on the sensitivity of an infrared detector with parametric frequency conversion

Numerical estimates are obtained of the sensitivity of near and middle infrared radiation detectors with parametric conversion of the signal frequency in crystals. Single-mode pumping with Gaussian fluctuations of the amplitude is assumed. It is shown that an increase in the pump fluctuations to 10% results in a deterioration of the threshold sensitivity by a factor of about 2 compared with nonfluctuating pumping.