High efficient and narrow linewidth fiber laser based on fiber grating Fabry-Perot cavity

A high Er3+-doped narrow linewidth fiber laser based on fiber Bragg grating Fabry-Perot cavity was demonstrated. The spatial hole burning effect was restrained by a fiber Faraday rotator. Two short fiber Bragg grating Fabry-Perot cavities as narrow bandwidth filters discriminated and selected laser longitudinal modes efficiently. A stable single-frequency 1534. 83 nm laser was acquired. Pumped by two 976 nm laser diodes and two-ended output, the fiber laser exhibited a 12 mW threshold. Total 39. 5 mW output power and one end 22 mW output power were obtained at the maximum 145 mW pump power. Optical-optical efficiency was 27% and slope efficiency was 29. 7%. The output power seemed to be saturated when pump power increased. The 3 dB linewidth of the laser was less than 7. 5 kHz, measured by the delayed self-heterodyne method with 15 km monomode fiber. The high power narrow linewidth fiber laser can be used in high resolution fiber sensor systems. © 2008 Higher Education Press and Springer-Verlag GmbH.