Improved Optical Pulse Characterization Based on Feedback-Controlled Hilbert Transformation Temporal Interferometry

We propose an accurate ultrashort optical pulse reconstruction method based on Hilbert transform temporal interferometry with a feedback control technique. The use of this feedback control allows us to minimize the phase measurement errors associated with instabilities in the fiber-based interferometry system, e.g., caused by environmental fluctuations. The method is experimentally demonstrated by precisely characterizing picosecond pulses after linear dispersion through short sections (30 ~ 700 m) of conventional single-mode fiber. A three-fold improvement in the phase measurement accuracy has been achieved using the feedback control technique.