Number of p-type distributed Bragg reflectors effects on gallium nitride (GaN)-based vertical cavity surface emitting laser performance

Abstract

This paper has presented the characteristic features of the reflectivity of the output mirror at 415 nm vertical cavity surface emitting lasers with various distributed Bragg reflectors pairs. For this, vertical cavity surface emitting lasers with various corresponding p-distributed Bragg reflectors pairs are simulated using integrated system engineering simulation program. The output power and the threshold current for each of these devices were determined. We found that by increasing distributed Bragg reflectors pairs, the distributed Bragg reflectors reflectivity increased, which can reduce the device lasing threshold. However, the external differential quantum efficiency was inversely related to top mirror reflectivity. So, the optical output of the device also decreased with increased p-type mirror pairs. A suitable distributed Bragg reflectors design is carefully selected for the pair number so as to balance among low lasing threshold current, high output power, and high efficiency. Key words: Semiconductor lasers, vertical cavity surface emitting laser, distributed Bragg reflectors, external quantum efficiency, multiple quantum well.