Effect of phase conjugate coupled on routes to chaos in incoherent optical feedback semiconductor quantum dot laser

The effect of the phase conjugate coupling on routes to chaos (mainly stable, sustained pulsating oscillations, evolves into double-period oscillation and quasi-periodic routes) in incoherent optical feedback semiconductor quantum dot laser is theoretically investigated using bifurcation diagrams, time series, attractors and inter-spike interval probability distribution. The parameter values of the coupling strength (η) and delay time (τ) (mirrors respond as fast and slow-response photorefractive mirrors) are modified to examine the sensitivity of routes to chaos with variation in the phase-conjugate mirrors. Both routes are found to be highly sensitive to the phase conjugate coupling effect. Instability and homoclinic chaotic can be observed in such a system.