Synchronization of semiconductor lasers with coexisting attractors

Area of Science:

• Nonlinear Dynamics
• Optical Engineering
• Laser Physics

Background:

• Optical bistable systems, particularly semiconductor lasers with external cavities, exhibit complex dynamics including fixed points, periodic orbits, and chaos.
• Understanding synchronization in such systems is crucial for applications in secure communications and optical computing.

Purpose of the Study:

• To investigate the synchronization phenomena in unidirectionally coupled optical bistable semiconductor laser systems.
• To analyze the influence of laser operating points and coupling strength on the synchronization routes.

Main Methods:

• Utilized model equations based on the Lang-Kobayashi approach to simulate laser dynamics.
• Employed a cross-correlation function to quantify the synchronization between master and slave lasers.

Main Results:

• Identified various bifurcations (Hopf, period doubling, saddle node, torus, crisis) leading to diverse dynamical regimes (steady state, periodicity, quasiperiodicity, bistability, chaos).
• Observed distinct synchronization behaviors influenced by operating parameters and coupling strength.
• Highlighted similarities and differences in synchronization between monostable and bistable laser systems.

Conclusions:

• Synchronization in coupled optical bistable lasers is a rich phenomenon governed by system parameters.
• The study provides insights into controlling and understanding complex dynamics in coupled laser systems for potential applications.