Research on Nonlinear Fiber Laser with Short Brillouin Gain Fibers

Nonlinear fiber lasers with short single-mode fibers (≤100m) are investigated. The effects of the length of the Brillouin gain fiber, i.e. the single-mode fiber, and the optical filter are studied. The experimental results indicate that the fiber laser can operate well with 50m single-mode fiber if the optical filter is adopted. But it cannot work when the single-mode fiber is shortened to 25 m. The results show that the nonlinear fiber laser based on single mode fibers as the Brillouin gain medium is hard to realize ultra-short (<; 10m) caivity, limiting its single-longitudinal-mode operation.