Generation of Time- and Wavelength-Interleaved Optical Pulse-Train With Tunable Pulsewidth Based on Dispersion and Sectional Compression

We show analytically as well as experimentally a technique to generate a time- and wavelength interleaved optical pulse-train (TWIPT) with tunable pulsewidth. The technique involves dispersing an initial pulse-train using a standard single-mode-fiber (SMF) followed by sectional dispersion compensation using a tunable multi-channel dispersion compensation module. Using an initial pulse-train with a fixed repetition frequency f_rep and a tunable multi-channel dispersion compensation module with a fixed frequency spacing between the adjacent channels, our scheme shows that by choosing appropriate value for the length of the SMF, we can generate a N×f_rep TWIPT in the case when there are N channels within the bandwidth of the initial pulses. By tuning the channel dispersion to be the opposite of the dispersion introduced by the SMF, one is able to generate transform-limited pulsewidths for the TWIPT. Furthermore, tuning the channel dispersion to other values permits pulsewidth tunability. Based on the proposed scheme, using a 2 GHz supercontinuum source as an initial pulse-train, we demonstrate the generation of a 10 × 2 GHz TWIPT with pulsewidth tunability.