Nonlinear Amplifying Loop-Mirror-Based Mode-Locked Thulium-Doped Fiber Laser

We present an SESAM mode-locked thulium-doped fiber laser incorporating nonlinear amplifying loop mirror with intracavity and external group velocity dispersion control, which generates sub-300-fs near-transform-limited pulses at 1920-nm wavelength, with 106-mW maximum average output power. The dispersion control was realized by implementing a low-loss highly doped germanium silica fiber.