Method of double-ring feedback phase-shift controlling chaos for dual-ring erbium-doped fiber laser

Two physical models of single-ring feedback phase-shift controlling chaos are discussed based on the method of chaos controlled by couplingfeedback phase-shift and its physical model. The coupler feeds the output back and the phase-shift controller controls the phase of feedback. Suitable feedback coefficient and apt feedback phase-shift can control the laser output into chaos state, stable state or periodic state effectively. Moreover, the paper analyzes the method of double-ring feedback phase-shift controlling chaos in detail, and the impact of feedback coefficient and feedback phase-shift on the model of double-ring is studied．