Nanosecond Pulse Generation in Lumped Normally Dispersive All-Fiber Mode-Locked Laser

We report an all-normal dispersion, all-fiber integrated ytterbium laser mode-locked by a single wall carbon nanotube (SWNT) saturable absorber, with a chirped fiber Bragg grating (CFBG) providing dispersion of 35.71 ps ·nm
^-1
allowing us to directly obtain nanosecond-scale duration pulses. In this large positive dispersion regime, mode-locking is initiated by the saturable action of the SWNT device, with pulse formation stabilized by the combined bandwidth limiting effect of the gain dispersion and the narrow reflection band of the CFBG.