Influence of facet reflection on the performance of a DFB laser integrated with an optical amplifier/modulator

The influence of output facet reflection on characteristics of a monolithically integrated optical device consisting of a distributed feedback (DFB) laser and an optical amplifier/modulator is analyzed. Basic equations used for the analysis are the characteristic equation for a DFB laser and the rate equations. As a result, it is known that static and dynamic properties of such optical integrated devices are seriously degraded by the optical feedback from the output facet. It is concluded that the power reflectivity of the output facet should be reduced to at least less than 0.1% for the integrated region to work as an optical amplifier and less than 0.01% as an intensity modulator.<
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