State-switchable Multi-wavelength and Dissipative Soliton Mode-locked Tm-doped Fiber Laser Based on a Combination of Nonlinear Amplifying Loop Mirror and Lyot Filter

This paper demonstrates a state-switchable Tm-doped fiber laser based on nonlinear amplifying loop mirror and Lyot filter technique. By properly adjusting the polarization controller and pump power, the Tm-doped fiber laser can operate in multi-wavelength state and dissipative soliton mode-locked state, respectively. And two types of operating states can be switched to each other. For multi-wavelength state, 8 stable wavelength peaks are generated within half of peak power variation. For the dissipative soliton mode-locked state, the dissipative soliton with pulse energy as high as 41.49 nJ, the pulse duration of 2.4 ns, and the spectrum bandwidth of 29 nm is generated at the center wavelength of 1 996 nm. The switching between different operating states is due to the change in the function of the nonlinear amplifying loop mirror caused by the polarization controller.