Spatially independent VCSEL models for the simulation of diffusive turn-off transients

Carrier diffusion and spatial hole burning can have a severe impact on vertical cavity surface emitting laser (VCSEL) performance. In particular, these phenomena can produce secondary pulses, bumps, and optical tails in the VCSEL turn-off transient which limit both the system bit rate and the bit error rate (BER). To study these effects, laser rate equation models that include both spatial and temporal dependence are often employed; however, simulations which require discretization of both space and time, while accurate, typically consume vast amounts of computational power. In this paper, we demonstrate that models based on well-accepted spatially independent rate equations can be used to simulate these effects. These models exhibit the advantages of the full spatio-temporal approach but execute much more quickly. We also integrate these models into electronic computer-aided design (CAD) tools which will enable circuit and system designers to simultaneously simulate electrical and optical performance.