Tunable Yb-Doped Double-Clad Fibre Laser Based on Fibre Bragg Grating with Narrow Linewidth

A tunable Yb-doped double-clad fibre (YDCF) laser by tuning the fibre Bragg grating (FBG) is successfully demonstrated. The FBG was fabricated in the YDCF directly, resulting in low splicing loss and compact configuration. A continuous tuning range of 15.6 nm from 1046.6 nm to 1062.2 nm is achieved. The laser linewidth is smaller than 0.1 nm in the whole tuning range. A maximum output power 117 mW is achieved when the pump power is 332 mW. The laser oscillation is quite stable in the whole operation.