Experimental evaluation of modulation induced by continuous waves in a semiconductor optical amplifier

Many simulative approaches have been proposed to investigate semiconductor optical amplifier (SOA) behaviour, in order to model its performance when used in several scenarios. Most of the applications of SOAs are based on the propagation of maximum two signals within the active medium, thus, higher order phenomena due to beating of more than two signals are not always correctly predicted by usual simulative models. In this paper we report some experimental results which validate an accurate model for SOA nonlinearities. This model is based on calculation of nonlinear susceptibility whose expression depends on multicarrier propagation. In particular, three signals are considered and their nonlinear interaction is evaluated by measuring a modulation arising on one of the signals.