Dynamical model of directly modulated semiconductor laser diodes

摘要

We present a new dynamical model for a directly modulatednsemiconductor diode, applicable to systems in which the dynamical timenscales of interest are longer than the round-trip time of light in thendiode. Employing a multiple scales analysis to simplify the familiarnphenomenological equations, we find that the dynamical response of thendiode can be described by time-dependent reflection and transmissionncoefficients for the electric field and one ordinary differentialnequation for the integrated carrier density. We do not assume that thenphoton and carrier densities are uniform along the diode and do not neednto calculate them explicitly at each point. Additionally, we need notnrestrict ourselves to only a small-signal response. We justify thenmultiple scales analysis for parameters corresponding to typicalnstructures through a comparison of the numerical solution of our resultsnand a direct numerical integration of the original phenomenologicalnequations