Modelling carrier dynamics and small-signal modulation response in quantum-well lasers

Abstract

This paper discusses models of carrier dynamics and modulation response in quantum-well lasers. We present a detailed carrier dynamics model that takes into account the different roles played by holes and electrons in such quantum-well lasers, the internal Coulomb field resulting from the mutual interaction of electrons and holes, and the effect of that field on the energy bands. We further address the ability to construct a simpler model that in the limited context of small-signal excitations yields results that are reasonably consistent with those of the detailed model. We compare that simple model to other common simple models and demonstrate the significance of identifying the important parameters in a simple model via self-consistent extraction from detailed calculations. We identify the equilibrium ratio of confined carriers to confinement region carriers, the local capture time and the transport time as the crucial parameters of any simple model.