Double-pumped fiber optical parametric amplifier with flat gain over 47-nm bandwidth using a conventional dispersion-shifted fiber

We investigate the performance of conventional dispersion-shifted fibers (DSFs) as nonlinear medium in double-pumped fiber optical parametric amplifiers (2P-FOPAs). We report on high gain (37 dB) with low ripple (±1.5 dB) over a 47-nm bandwidth using these fibers. We show that the 2P-FOPA average gain and the gain uniformity are limited by longitudinal variations of the zero dispersion wavelength and by polarization-mode dispersion. We demonstrate that 2P-FOPAs constructed with DSFs exhibit negligible crosstalk even for high gains (40 dB) and large output signal powers (12.5 dBm) in a ten-channel system.