All-Fiberized Passively Q-switched Fiber Laser And Supercontinuum Generation

All fiberized laser technology is one of the most important technologies in laser, due to its important application in optical fiber sensing, optical fiber communications, manufacture industry and so on. This thesis focuses on research of all fiberized fiber laser technologies, which include passively Q-switched fiber laser with FSA, quick passively Q-switched fiber laser based on SBS effect and supercontinuum generation in Bi/Cr co-doped fiber.A novel Bi/Cr co-doped fiber acting as a saturable absorber has been demonstrated. By splicing 12cm Bi/Cr co-doped fiber in a laser cavity, we achieved a passively Q-switched fiber laser. Pulse output at 1061nm was obtained with around 500ns pulse duration and more than 50% optical to optical conversion efficiency.We also demonstrates a novel all-fiberized Yb doped fiber laser configuration for passively subnanosecond pulse generation. By splicing a piece of short Bi/Cr codoped silica fiber to a section of Yb doped double cladding fiber of 15 meters in a fiber Bragg grating constructed fiber laser cavity, stable subnanosecond pulse train was experimentally obtained with a maximal repetition rate of 50.2 kHz and an average power output of 2W. The caculated peak power exceeded 30kW. The linear dependence of the pulse repetition rate on the absorbed pump power was confirmed. It was also found that the Stimulated Brillouin Scattering plays a crucial role in the pulse generation.A supercontinuum source has been demonstrated with Bi/Cr co-doped fiber. Broadband infrared supercontinuum emission was detected via the Bi/Cr fiber end, which spanned over 1000 nm with spectral intensity variation lower than 5 dB.