Chaotic dynamics of Pr ³⁺ /Yb ³⁺ -doped all-fiber up-conversion visible fiber laser

Abstract We investigate theoretically and experimentally the chaotic dynamics of visible-wavelength all-fiber ring laser. The 100-m 630 HP fibers are used to ensure high non-linearity. A 4-m Pr 3+ /Yb 3+ -co-doped ZBLAN fiber provides the gain. The chaotic laser was pumped by the laser diodes with the maximum power of 150 mW at the wavelength of 850 nm. The peak fluorescence spectrum of Pr 3+ /Yb 3+ -co-doped ZBLAN fiber at the wavelength of 635 nm shows that the visible-wavelength fiber laser can be achieved by synergistic energy transfer between Pr 3+ and Yb 3+ ions. The chaotic fiber laser is generated by adjusting the pump power, polarization controller and the auto-correlation, permutation entropy, skewness, and kurtosis were used to analyze the characteristics of chaotic laser. The noise-like time series and delta-like auto-correlation curve indicate the chaotic output. The complexity and randomness of time series are analyzed by the permutation entropy, skewness, and kurtosis. The result shows that chaotic dynamics is stable when the pump power exceeds a certain value. The visible chaotic all-fiber laser has high stability and can be applied for real-time monitoring and sensing. We believe that this approach may also be feasible for other materials for emission in the visible range.