We demonstrate a compact tunable and switchable dual-wavelength fiber laser based on the Lyot filtering effect and the spontaneous radiation peaks of gain fiber. By introducing a period of polarization-maintain Er-doped fiber (PM-EDF), stable dual-wavelength pulses can operate in both the anomalous dispersion region and the normal dispersion region. The corresponding repetition frequency difference of the dual wavelengths has excellent stability while the relative center wavelength can be adjusted in the range of 5 nm to 13 nm. There is no existence of significant sidebands in the optical spectrum during the whole tuning process. This dual-wavelength laser based on two spontaneous radiation peaks in the shorter wavelength direction has great application potential. Our work provides a new design solution for dual-comb sources (DCSs).

We report a Yb-doped mode-locked fiber laser based on a nonlinear amplifying loop mirror (NALM), which is all-normaldispersion (ANDi), and allows the output wavelength to be tunable. The laser can generate a stable femtosecond dissipative soliton with a maximum output power of 196 mW. Its repetition rate is 112.4 MHz, and the final pulse duration is 236 fs. By adjusting the angle of the reflective diffraction grating, the mode-locked fiber laser was realized to tune the output with a tuning range of 54 nm from 1011.8 nm to 1065.6 nm. To the best of our knowledge, this is the widest tuning range of an ANDi Yb-doped mode-locked fiber laser based on NALM.

No abstract

No abstract

No abstract