Generalized coupled-mode model for the multistripe index-guided laser arrays

We develop a generalized coupled-mode model for multistripe index-guided laser arrays that includes explicitly the influence of carrier-induced antiguiding, gain guiding, and carrier diffusion in the gain stripe. As an illustration of an application of the model, stability criteria for two-element laser arrays are derived that show that the phase-locked solution is intrinsically unstable. We find that the phase-locked solution can be stabilized at a low external injection-locking power at the suitably chosen injection-locking frequency. We have tested our model in the large carrier-diffusion case and still find good qualitative agreement between the coupled-mode model and a full coupled partial differential equation model.