Impact of Bottom DBR Radius and Electric Aperture Radius on GaN VCSEL Operation

We present the results of a numerical analysis of a nitride-based vertical-cavity surface-emitting laser (VCSEL) with an upper mirror composed of a monolithic high-contrast grating (MHCG) and with a bottom dielectric mirror. Using numerical simulations, we investigated the impact of the size of the lower dielectric mirrors on laser performance. Additionally, we examined the effect of changing the electrical aperture radius (active area dimensions) of the laser. Based on the obtained results, we demonstrated that the appropriate selection of these two parameters allows, among other benefits, the reduction of the temperature inside the laser, the lowering of the laser's threshold current, and a significant increase in its optical power.