Synchronization of optical-feedback-induced chaos in semiconductor lasers by optical injection

We study the synchronization of feedback-induced chaos in semiconductor lasers by the optical injection scheme that consists of a transmitter laser with external optical feedback and a receiver laser with optical injection from the transmitter laser. The stable synchronization condition and the effects of the frequency detuning between the transmitter and the receiver lasers are investigated using numerical simulation. The results show that positive and negative frequency detuning exert different influences on the synchronization. A time lag between the waveforms of the transmitter and the receiver lasers in the case of a large frequency detuning is found and its experimental significance is commented on.