Balanced photodetectors nonlinearity for short-pulse regime

TL;DR

This paper investigates the nonlinear response of balanced photodetectors when used with short pulse lasers, revealing nonlinearities occur below the saturation threshold due to pulse effects.

Contribution

It provides a detailed characterization of two common balanced detectors' nonlinearities in the short-pulse regime, highlighting the impact of pulse dynamics.

Findings

Nonlinearities occur even below the saturation threshold.

Pulse characteristics significantly influence detector response.

Balanced detectors' impulse response mismatch affects performance.

Abstract

Short pulse lasers are used to characterize the nonlinear response of amplified photodetectors. Two widely used balanced detectors are characterized in terms of amplitude, area, broadening, and balancing the mismatch of their impulse response. The dynamic impact of pulses on the detector is also discussed. It is demonstrated that using photodetectors with short pulses triggers nonlinearities even when the source average power is well below the detector continuous power saturation threshold.