Optimizing chaos time-delay signature in two mutually-coupled semiconductor lasers through controlling internal parameters

In this contribution, the effects of two key internal parameters, i.e. the linewidth-enhancement factor [Formula: see text] and gain nonlinearity [Formula: see text], on time-delay signatures (TDS) concealment of two mutually-coupled semiconductor lasers (MCSLs) are numerically investigated. In particular, the influences of [Formula: see text] and [Formula: see text] on the TDS concealment are compared and discussed systematically by setting different values of frequency detuning [Formula: see text] and injection strength [Formula: see text]. The results show that the TDS can be better suppressed with high [Formula: see text] or lower [Formula: see text] in the MCSLs. Two sets of desired optical chaos with TDS being strongly suppressed can be generated simultaneously in a wide injection parameter plane provided that [Formula: see text] and [Formula: see text] are properly chosen, indicating that optimizing TDS suppression through controlling internal parameters can be generalized to any delayed-coupled laser systems.