Superhigh differential quantum efficiency and strong self-sustained pulsation in CW DH laser diodes

Some experimental results in GaAs DH lasers having a stable, long operating-time, such as nonlinear superhigh differential quantum efficiency, the behavior of light output saturation and sudden growth again in the same filament, strong self-sustained pulsation, and so on, are presented. A model of double filaments caused by the non-uniform distribution of aluminum in the active layer of the laser diode is presented to explain their anomalous behavior qualitatively.