Harmonic distortion in SOA based slow/fast light microwave photonic phase shifters

We address theoretically and experimentally the generation of harmonic distortion in a SFL phase shifter based on CPO in a SOA device. The topic is of importance in the context of microwave photonics for two reasons. First of all, it provides useful guidelines for the proper design of distortion-free SFL tunable phase shifters. In second place, it allows us to explore for the possibility of designing upconverting devices where the phase of the upconverted signal can be tuned, a unique feature to the best of our knowledge.