Picosecond and Sub-Picosecond Flat-Top Pulse Shaping Using Abrupt Taper Interferometers

A picosecond flat-top pulse shaper using an abrupt taper interferometer is proposed and experimentally demonstrated. A theoretical model based on coupled mode equations is also derived to simulate the propagation of picosecond pulses through the abrupt taper interferometer. Through properly designing the abrupt taper interferometer, a 3.8-ps flat-top pulse with less than 4% ripple is successfully generated from a 2.2-ps Gaussian pulse. The proposed technique can also be used in the sub-picosecond regime.