Characterization of a Monolithic Concatenated SOA/SA Waveguide Device for Picosecond Pulse Amplification and Shaping

In this paper, a monolithic waveguide device, named IRIS, is presented. The device consists of an array of concatenated semiconductor optical amplifiers and saturable absorbers. We have fabricated the devices in InP-InGaAsP bulk gain material and we have experimentally investigated picosecond pulse transmission through these devices. Operated as an optical amplifier the IRIS devices show a decreased temporal pulse broadening and decreased amplified spontaneous emission noise generation as compared to a semiconductor optical amplifier of equivalent length. Used as a nonlinear element to increase the optical bandwidth of a picosecond pulse train, the spectra obtained with IRIS devices show an increased broadening and smoothness as compared to a semiconductor optical amplifier. We have set up a theoretical model to describe spectral and temporal pulse shaping by the IRIS device. Agreement between the simulations and the experiments is obtained.