Timing jitter of ultrashort solitons in high-speed communication systems I General formulation and application to dispersion-decreasing fibers

Abstract

By using adiabatic perturbation theory, we calculate the timing jitter generated by fluctuations in soliton amplitude, frequency, and position that are induced by the amplifiers noise in high-speed soliton communication systems. The analysis is applied to dispersion-tailored fibers which, in contrast with conventional constant-dispersion fibers, allow ultrashort solitons (width <10 ps) to propagate over long distances with minimum production of dispersive waves. We show that a transition from a regime in which amplifier noise-induced frequency fluctuations dominate the timing jitter (Gordon–Haus jitter) to a regime in which amplitude fluctuations dominate the timing jitter occurs when solitons become shorter than 2–7 ps, depending on the total distance of transmission. The latter source of jitter arises because fluctuations in the soliton amplitude are converted to frequency fluctuations by the Raman effect, which in turn are converted to position fluctuations by the group-velocity dispersion. The contribution of third-order dispersion to the timing jitter is evaluated and discussed. We provide an estimate of the distance at which soliton-control elements (such as synchronous modulators) should be inserted to reduce the timing jitter and extend the transmission distance.