Liquid saturable absorber mode locking optical fiber laser

The invention relates to a liquid saturable absorber mode locking optical fiber laser, and belongs to the technical field of optical fiber lasers. According to the liquid saturable absorber mode locking optical fiber laser, a liquid saturable absorber is utilized to serve as a mold locking element, so picosecond or femtosecond ultrashort pulse outputting is achieved. According to the technical scheme, an annular laser resonant cavity is adopted, the resonant cavity is formed by a pumping source, a wavelength division multiplexer, a gain optical fiber, a single mode optical fiber, an isolator, a liquid saturable absorption device and an output coupler, and the liquid saturable absorption device is formed by a liquid saturable absorber and an optical fiber connecting container. The liquid saturable absorber mode locking optical fiber laser is characterized in that a carbon nanotube or grapheme is adopted in the liquid saturable absorption device to serve as a saturable absorption material, and the saturable absorption material is mixed into distilled water or heavy water to serve as the saturable absorber. The saturable absorption material has mobility in liquid, and the liquid has radiation effects on the material. Therefore, the mode locking optical fiber can work stably under high power for a long time.