All-fiber tm³⁺-doped fiber Laser Using Pump Combiner and Fiber Bragg Grating Inscribed by Femtosecond

All-fiber Tm³⁺-doped fiber laser can be used as the pumping for (Optical Parametric Oscillator, OPO), realizing 3 ~ 5 μm laser output. All-fiber Tm³⁺-doped fiber laser was demonstrated more excellent application prospects in lidar and electro-optical countermeasure. An all-fiber cladding-pumped Tm³⁺-doped fiber laser using pump combiner and double-cladding fiber isreported.Thepumpcombineranddouble-claddingfiberarehome-made.Home-madefiberbragg grating (FBG) is used as reflection cavity. The double-cladding fiber is cooling by water. The fiber Bragg grating is directly written in the Tm³⁺-doped fiber through 45 fs,800 nm femtosecond and a phase mask. The combiner is used to launch the pump light into the Tm-doped inner-cladding fiber. The wavelength of the laser is about 1. 96 μm with a slope efficiency of 37% in respect to the launched pump power,the linewidth is narrow only about 72. 4 pm.