Impact of Dispersion Fluctuations on Dual-Pump Fiber-Optic Parametric Amplifiers

Abstract—Effects of zero-dispersion wavelength (ZDWL) fluc-tuations on dual-pump fiber-optic parametric amplifiers are inves-tigated analytically and numerically. It is found that the signal gain varies considerably from fiber to fiber even though each fiber may have the same ZDWL on average. Moreover, the gain spectrum be-comes highly nonuniform for a given fiber because of such disper-sion fluctuations. Numerical simulations show that this problem can be solved to a large extent by reducing wavelength separation between the two pumps, but only at the expense of a reduced am-plifier bandwidth. Index Terms—Dispersion fluctuations, four-wave mixing (FWM), parametric amplification. F IBER-OPTIC parametric amplifiers (FOPAs), based onfour-wave mixing (FWM), can provide uniform gain over a relatively wide bandwidth when they are pumped at two wavelengths located on each side of the zero-dispersio