Experimental study of stability properties of injection-locked InGaAsP/InP laser diodes

Single-mode operation of the laser is a basic condition in an optical wide-band transmission link. Lasers stabilized by injection locking showed excellent side-mode suppression. Slight detunings within the locking range between the master laser and slave laser caused by modulation, bias current variations or optical feedback led to unstable behaviour and disturbed the BER of a 1.12 Gbits^–1 transmission experiment via a 21-km single-mode fibre.