Influence of scattering effects on the interaction between longitudinal modes in laser diodes

Abstract

A predictive model of scattering processes in semiconductor lasers is derived, enabling us to model relaxation processes starting from well-known parameters such as the dielectric constant. The resulting effective mode interaction terms are explicitly calculated for an (InGa)N quantum well using Coulomb scattering. In contrast to the method used so far to model mode competi- tion phenomena in Fabry--Pérot type laser diodes, the model correctly includes e.g. accelerated scattering at higher densities or temperatures and eliminates the scattering rate as an unknown parameter. The effective mode interaction term derived in this work can be used for the simulation of the mode dynamics in various laser diode types, for example broad area laser diodes, where multiple transversal and longitudinal modes are active. Thus, our model offers an increased pre- dictability and improved modelling of switch-on behavior.