Injection Power and Detuning-Dependent Bistability in Fabry–Perot Laser Diodes

In this paper, we investigate the range of injection power and frequency detuning for which bistability of the injection-locked semiconductor Fabry-Perot laser diode can be achieved and preserved. The analysis is based on a detailed model of the multimode rate equations and material gain. The stationary analysis shows that there is a region of the injection power and detuning for which the laser has three stationary states. However, the stability analysis shows that for a wide range of injection powers and detuning, the two of three stationary states are stable and provide bistability. One of these states is the result of injection locking, whereas the other is mainly a consequence of the interplay between injection-locked and unlocked modes. The difference of the side-mode-suppression ratio between the stable states is of the order of 20 dB and it can increase with detuning and decrease with mode order.