A Simple Iterative Model for Oxide-Confined VCSELs

A simple iterative model is developed for the analysis of the current distribution in multi-mode vertical cavity surface emitting lasers (VCSELs) using a SPICE-like approach. The model includes the measured sheet resistances as input parameters, drift-diffusion for lateral carrier transport, and a degeneracy correction for the above threshold condition. The effect of the resistance due to the oxide layer on performance is investigated. Higher sheet resistance under the oxide layer reduces the threshold current, but reduces the current range over which single transverse mode operation occurs. The voltage drop across the p-DBR region dominates spatial hole burning, which is moderated by lateral drift and diffusion of carriers. This simple iterative model is applied to commercially available oxide- confined VCSELs.