Numerical analysis of broadband fiber optical parametric amplifiers pumped by two chirped pulses

An optical parametric amplifier pumped by two chirped pump pulses has been analytically and numerically investigated to predict the spectral gain bandwidth and its temporal distribution. We highlight that the properties of the amplifier depend strongly on the relative chirp values and a uniform spectrotemporal gain can be obtained when the two chirps have opposite signs. A chirped signal pulse owing a very broad bandwidth has also been injected and we demonstrate the amplification of ultrashort pulse with this type of amplifier. (C) 2016 Optical Society of America