Tunable and switchable single-/dual-wavelength Er-doped hybrid mode-locked fiber laser by dual-PMFs Lyot filter

We propose a single- and dual-wavelength tunable and inter-soliton switchable Er-doped hybrid mode-locked fiber laser based on dual-polarization maintaining fibers (dual-PMFs) Lyot filter. The broadband saturable absorber was constructed by WS2/MoS2 nanocomposite and nonlinear polarization rotation (NPR) effect. The transmission characteristics of the dual-PMFs Lyot filter were theoretically analyzed, and the single- and dual-wavelength tunable spectra were obtained experimentally. Moreover, the switchability of single and bound solitons was investigated through inter-soliton interactions, and the bound solitons and the bound states of bound solitons in the single- and dual-wavelength mode-locked laser were generated and analyzed. These indicate that the tunable and switchable fiber laser has a wide range of applications and important research implications in ultrafast photonics. It also provides new insights and development for the application of two-dimensional nanocomposites in ultrafast photonics.