Features of a semiconductor optical amplifier/saturable absorber module in signal transmission lines

Summary form only given. Saturable absorbers (SA) are extensively used for passive mode locking in ultrashort pulse lasers. Their particular features can be likewise exploited for increasing the transmission capacity in long haul fiber networks where gain is provided by semiconductor optical amplifiers (SOA). An integrated single chip SOA-SA module (SOASA) is particularly useful and can be manufactured by ion-implantation through one facet of a bulk laser diode chip with antireflection coatings on both sides. In order to maximize the transmission capacity an analytical model is required that describes the SOASA single pulse response as a function of relevant system and signal parameters. To achieve this goal we used the model established previously. This SOASA module was likewise used in our experiments. The crucial system parameters of the model are recovery time, saturation energy, small signal gain and Henry factor of both the SOA and the SA section. Based on the analytical response function expressions for temporal walk off, energy gain and spectral shift can be obtained.