An Iterative Model for the Steady-State Current Distribution in Oxide-Confined VCSELs

This paper presents an iterative model for the analysis of the current distribution in vertical-cavity surface-emitting lasers (VCSELs) using a SPICE-like approach. The model includes a degeneracy correction for operation at and above threshold. The effect of the resistance due to the p-distributed Bragg reflector (p-DBR) mirror layers and 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. This simple iterative model is applied to commercially available oxide-confined VCSELs.