Theoretical And Experimental Research Of Erbium-doped Fiber Laser

Narrow linewidth fiber laser has been widely used in long distance transmission and high resolution analysis for optical spectrum. What is more, it's also the necessarily light source for M-Z interferometer sensor. This article mainly focused on the way to get the low linewidth output laser.The following is exactly what i have done in the past several months:1.I have announced one new structure for fiber laser in my article, using FBG F-P etalon and FBG Sagnac ring to be the optical filter. Because of their great filtering performance, which are good for narrow linewidth output laser.2. Through the coupled mode equation., I got to know the transmission formula of FBG F-P etalon and FBG Sagnac ring. In the end, I analysed this reflection formula of FBG F-P etalon and FBG Sagnac ring.with MATLAB and made a research of all the key point which would have some impact on the FBG F-P etalon' and FBG Sagnac ring's transmission characteristics:3. Through all the work mentioned, I got exactly the parameter of FBG F-P etalon and FBG Sagnac ring. Now it is time to achieve my ring cavity fiber laser. Based on the rate equation and propagation equation, the threshold power expression and the output power's expression can be worked out. At last, I made a comprehensive analysis of the ring cavity fiber laser with FBG F-P etalon and FBG Sagnac ring with MATLAB.4. Based on the equipment of our lab, a kind of erbium-doped fiber laser was accomplished. With the fiber length is 6.5m, its threshold power 15mw,slope efficiency of 32% and a Side Mode Suppression Ratio of over 50dB, its linewidth was lower than O.lnm and The range of wavelength shift is smaller than O.Olnm.