All-PM Fiber Thulium-Doped Mode-Locked Fiber Laser and Amplifier Based on Nonlinear Loop Mirror

The broadband gain bandwidth of thulium-doped fibers ranging from 1.8 to 2.1 μm makes them an excellent choice for the generation of ultrafast mode-locked pulses in the mid-infrared spectral region. Therefore, ultrafast lasers operating at 2 μm have attracted significant interest in the research community in recent years due to their wide range of applications including medicine, material processing, spectroscopy, remote sensing, and supercontinuum generation [1-3]. To date, many different configurations for passively mode-locked thulium-doped fiber lasers (TDFL) have been proposed. In order to develop a self-starting and environmentally stable ultrafast laser we use an all-PM-fiber technology and a nonlinear fiber loop mirror [4] (NOLM) as an artificial saturable absorber.