Theoretical and experimental investigations of the temperature dependent continuous wave lasing characteristics and the switch-on dynamics of an InAs/InGaAs quantum-dot semiconductor laser

We investigate spectrally resolved continuous wave (CW) and spectrally and time-resolved switch-on emission properties of an InAs/InGaAs quantum-dot laser. The temperature and injection current dependence of the excited-state and ground-state emission dynamics is studied in the range between 20 °C and 50 °C under CW and gain-switching operation. All the experimental results are found to be in good agreement with simulation results based on a multi-population rate equation model incorporating all of the peculiar properties of the quantum-dot material as homogeneous and inhomogeneous broadening of the emission linewidth, different dynamics for electrons and holes, cascaded and direct capture paths of carriers from the wetting layer into the dot and Auger non-radiative recombination. This coincidence between simulations and experiments allows explaining the complicated behavior of the CW characteristics and the switch-on dynamics in the investigated temperature range.