Study of the characteristics of 976 nm Bragg grating external cavity semiconductor lasers

976 nm fiber Bragg grating (FBG) external cavity laser is the core component in erbium-doped fiber amplifiers (EDFA). In this paper, the theory model of FBG is modeled by transfer matrix method (TMM). The effects of Bragg grating length and modulation depth on the reflectivity, grating spectrum width and wavelength have been investigated. Then 976 nm laser modules with different grating reflectivity, i.e. 4%, 6%, 8% and 10% have been fabricated. By improving the reflectivity of FBG, the side-mode suppression ratio (SMSR) has been optimized to above 40 dB, and the threshold current decreases. The temperature cycling test indicates that the peak wavelength has a change rate [Formula: see text]0.0095 nm/[Formula: see text]C.