Different kinds of bistable behaviour of a GaAlAs diode coupled to an external cavity of variable length

摘要

Experiments and theory on optical feedback effects for different delay times in a system consisting of a GaAlAs-DH diode coupled to an external resonator are presented. Two hysteresis types are found, for short and long delay times. In the case of short optical delay the low-power hysteresis branch corresponds to the noise level below the lasing threshold, whereas for a long delay regular or irregular pulsations of considerable mean power occur. On the upper power level c.w. single-mode emission is dominant for both of the hysteresis types. Dynamic losses due to spectral bandwidth changes may explain the different behaviour.