Modulation characteristics of self-assembled InAs-GaAs quantum dot laser considering phonon bottleneck, carrier relaxation and homogeneous broadening

The effects of carrier dynamics on the frequency response of self-assembled quantum dot laser (SA-QDL) are presented. The phonon bottleneck effect on modulation response is simulated. It is shown that to prevent the effect of phonon bottleneck on the frequency behaviour, carrier relaxation lifetime must be less than a certain critical value which is in agreement with the experimental results. Results show that carrier recombination in wetting layer has no important effect on the modulation response, however, carrier recombination inside dots degrade frequency response drastically. The influences of homogeneous broadening as well as pumping current on the frequency characteristics are also investigated.