Impact of dispersion fluctuations on dual-pump fiber-optic parametric amplifiers

Effects of zero-dispersion wavelength (ZDWL) fluctuations on dual-pump fiber-optic parametric amplifiers are investigated 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 becomes highly nonuniform for a given fiber because of such dispersion 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 amplifier bandwidth.