Small-signal dynamic response of quantum-dot lasers with asymmetric barrier layers (Conference Presentation)

The small-signal dynamic response of quantum dot (QD) lasers with asymmetric barrier layers (ABLs) is studied. The modulation bandwidth of this novel type of laser is shown to have a maximum as a function of the dc component of the pump current and parameters of the structure. This provides a clear path for optimizing the laser structure to enhance its bandwidth. The effect of non-instantaneous capture of electrons and holes into QDs on the modulation bandwidth is studied. The maximum bandwidth and the optimum dc injection current at which it is attained are calculated as functions of the capture cross-section. The optimum dc injection current is shown to be considerably lower in ABL QD lasers as compared to conventional QD lasers, i.e., the maximum bandwidth is easier to attain in ABL QD lasers.