Synchronization Regime of Star-Type Laser Network With Heterogeneous Coupling Delays

The synchronization properties and the sensitivity of generalized lag synchronization (GLS) in all-optical star network with mutually coupled semiconductor laser in the presence of heterogeneous delays are investigated numerically. The hub node and the side nodes are optically coupled with asymmetrical injection strength. The dependence of GLS on the effects of lasers' pump current, injection strength, asymmetrical injection factor, and frequency detuning distribution is examined. It is found that, except for the injection strength and frequency detuning, the pump current of hub laser and the asymmetrical injection factor are also key factors that determine the quality of GLS in star network with heterogeneous delays. Extremely asymmetrical injection as well as large pump current of hub laser is suggested to obtain high-quality GLS in wide parameter regions. Such GLS can also be obtained in a large-scale laser network with heterogeneous coupling delays, and is hardly affected by the time delay distribution, which opens possibilities for multi-user chaotic communication and synchronization-based secure key distribution network among the side nodes.