Vector Signal Characterization of High-Speed Optical Components by Use of Linear Optical Sampling With Milliradian Resolution

We demonstrate linear optical sampling measurements optimized for characterization of the signals produced by optical components. By sampling the optical electric field before and after the component, we isolate the full vector field (phase and amplitude) of the signal separate from the input laser drift. Synchronization of the low-jitter mode-locked sampling laser (e.g., frequency comb) with the modulation rate allows measurement of the phase with milliradian noise. As a demonstration, we measure 10-Gb/s differential phase-shift keying modulated data with several different lasers. The technique is readily scalable to systems of much higher bandwidth.