Ultrashort Flat-Top Pulse Generation Using On-Chip CMOS-Compatible Mach–Zehnder Interferometers

Reshaping of an ultrashort Gaussian-like pulse into a flat-top pulse is demonstrated using an integrated Mach-Zehnder interferometer (MZI). The 7.8-ps Gaussian-like pulses are reshaped into nearly chirp-free 17.1-ps and 20.0-ps flat-top-pulses based on two different linear filtering schemes. In addition, the capability of this integrated MZI to generate a Hermite-Gaussian pulse with duration of a few picoseconds is demonstrated.