Degradation-induced microwave oscillations in double-heterostructure injection lasers

Abstract

Microwave oscillations in the light output of mesa-stripe GaAs–Ga1−xAlxAs double-heterostructure lasers have been observed after degradation. The same lasers showed no oscillations before degradation. The experimental evidence indicates that the oscillations are caused by repetitive Q switching, with dark-line regions in the degraded units acting as saturable absorbers.