Measurement of pulse amplitude and phase using cross-phase modulation in microstructure fiber

Cross-phase modulation in a highly nonlinear microstructure optical fiber with low dispersion and high birefringence is used for the measurement of the pulse amplitude and phase of picosecond pulses by frequency-resolved optical gating. An alignment-free configuration including an optical amplifier is proposed and experimentally tested. The simulated annealing method is used for retrieving the amplitude and phase from cross-phase modulation spectrograms. It takes into account the birefringence of the measurement fiber and the resolution of the optical spectrum analyzer.