Controlling chaotic behaviour in erbium-doped fiber dual-ring laser with coupling feedback

A method of controlling chaotic behavior in erbium-doped fiber dual-ring laser is proposed by using couplers to feed the laser outputs back into the system and control the decay rate of the system indirectly. The chaotic fiber laser is controlled by selecting appropriate feedback coefficients which are defined by the decay rate and the coupling coefficient of the system. The simulation results show that couplers are used to modulate the decay rate and the feedback coefficient, and the chaotic fiber can be controlled into the single-leriod, dual-period and stable states respectively. The larger the feedback coefficients is, the faster the laser enters into a stable state.