Timing jitter in modelocked lasers

To obtain a better understanding of the influence of active modulation, we have performed studies of timing restoration dynamics in a modelocked Er-doped fiber ring laser Amplitude modulation retimes displaced pulses via a simple exponential time constant. Phase modulation produces frequency shifts that lead to retiming via group velocity dispersion. It produces an oscillatory timing recovery that is damped by filtering. The time constants obtained from these results can be used in conjunction with the analytical theory to better understand measurements of steady state jitter and to help optimize laser design for minimum jitter.