Mutual coherence and chimera states from interacting self-pulsing laser cavity solitons

Abstract The mutual coherence of self-pulsing laser cavity solitons in broad-area semiconductor lasers with an intra-cavity saturable absorber is investigated through numerical simulations. This study explores various interaction modes and configurations, specifically 1D binary and 2D ternary arrangements. The findings demonstrate that these solitons can function as coherent sources of radiation when they achieve in-phase synchronization. We also report the emergence of chimera states in a chain of interacting self-pulsing laser cavity solitons where it is possible to switch between two different types of chimera state by an easily accessible control parameter, e.g., pump current. These chimera states can be viewed as originating from two distinct symmetry breaking events: temporal symmetry breaking associated with a Q-switching instability of the stationary soliton and spatiotemporal symmetry breaking where identical oscillators spontaneously separate into synchronized and de-synchronized subpopulations despite homogeneous coupling. These findings provide new insight into the collective dynamics and coherence control of localized self-pulsing structures in nonlinear photonic systems.