ANALYTICAL EXPRESSIONS FOR THE FM AND AM RESPONSES OF AN INTEGRATED LASER-MODULATOR

The need for low-chirp and compact transmitters for high-bit-rate opti cal links has led to the development of integrated laser electroabsorp tion modulators (ILM). We have investigated feedback effects inducing frequency chirp by developing a model treating the ILM as a whole and obtained analytical expressions of the FM and AM responses. The variat ion of the frequency chirp with the residual facet reflectivity of the modulator section is calculated. The model predicts the unusual peak in the measured frequency responses and has been used to define design rules.