Tunable Wavelength generation from PM Yb-doped fiber laser modelocked by NAbLM

In this work, an all-fiber, polarization-maintained, Nonlinear Absorbing Loop Mirror-based modelocking in a Ytterbium-doped double-clad fiber laser was realized in a Figure-of-8 architecture. This was achieved by utilizing an asymmetrically placed gain fiber (absorber) of 1.5 m in the nonlinear loop. This resulted in stable mode-locked pulses having an average power of \((\sim)\) 20 mW, with a Signal-to-Noise ratio of more than 60 dB, a linearly chirped pulse duration of 30 ps and a repetition rate of 11.35 MHz. The central wavelength was observed to be tunable with respect to the instantaneous intracavity power, ranging from 1048 to 1069 nm, representing the largest tunable range reported to date for a polarization-maintained all-fiber Figure-of-8 laser, to the best of our knowledge. The tunable output obtained from this Nonlinear Absorbing Loop Mirror architecture was also compared to a more conventional Nonlinear Optical Loop Mirror-based oscillator.