Ytterbium fiber laser based on fiber Bragg grating inscribed point-by-point with femtosecond laser

A fiber Bragg grating(FBG) was inscribed into Corning Hi1060 fiber by focused irradiation of 800 nm femtosecond laser pulses. The FBG was 8 mm long with the period of 2.9 μm, which corresponds to an eight-order grating for 1 042 nm. As the output coupling mirror, the FBG was spliced to a 3 m long double-clad fiber to form the cavity of a fiber laser. A 975 nm laser diode fiber module was used as the end-pump light source. The double-clad fiber was provided by Nufern, with the core and cladding diameters of 10 μm and 125 μm, respectively. The laser output power was 71.1 mW in our experiment, and the center wavelength was 1 042 nm, with the bandwidth of 0.8 nm.