Strong optical injection locked semiconductor laser for high bit rate chaotic optical communications


Abstract: We present in this article how strong optical injection can produce chaotic dynamics in the output of the semiconductor laser that is preferable for perfect encrypted optical communication networks. Significant increase in the relaxation resonance frequency was found implying higher degree of enhancement in modulation bandwidth. Numerical investigations under the condition of strong optical injection locking of the slave laser shows that instabilities in the photon number was observed and had settled down after a time of in the order of carrier lifetime. The model presented can be used to extract the characteristic parameters of the injection locking for detuning of the system. Optimum value of nonlinear gain and linewidth enhancement factor were found to have an impact on the chaotic dynamics of the slave laser. A layout for optical communication network using Optisystem 7.0 simulation software with slave laser as a transmitter undergoing strong optical injection locking will be illustrated for high bit rate. Chaos at high modulation frequency in the output power of the slave had been established in the simulations predicting the validity of the model for secure optical communications.

Keywords: Injection locking, laser diode, optical communications, chaos

Full Text: PDF