Investigation on chaotic dynamics of ytterbium-doped fiber laser with Mach–Zehnder interferometer

Abstract

Chaotic dynamics are observed experimentally from an ytterbium-doped fiber laser when the polarization controller is adjusted to an appropriate position and the pump power is increased. But chaotic signals hide the cavity-length signature of ytterbium-doped fiber laser and the cavity-length can be identified by the sidelobes of chaotic autocorrelation. The perturbation of variable optical attenuator inserted to the ytterbium-doped fiber laser and the interference effect induced by the optical path difference (OPD) of a fiber optical Mach–Zehnder interferometer (MZI) are adopted to investigate the chaotic dynamics. The results show that such sidelobes can be completely suppressed by exerting the perturbation and by the interference effect of MZI with optimum OPD which is demonstrated theoretically and experimentally. Moreover, the optimum OPD corresponding to the delay-time of MZI is intimately related to the relaxation oscillation period.