LAUSR

GaN-based laser diodes transform only a relatively small fraction of the electrical input power into laser light. The inherently large series resistance of these devices causes significant self-heating that leads to the typical power roll-off at high current. We analyze recently reported measurements using advanced numerical laser simulation and investigate the physical mechanisms that limit the lasing power in continuous-wave operation. Contrary to common expectations, our analysis reveals a strong influence of Auger recombination since the self-heating leads to a rising quantum well carrier density above the lasing threshold. As possible remedy, we investigate the effect of a tunnel-junction contact and predict a significant enhancement of lasing power and efficiency.