1018nm Yb-doped Fiber Laser

Yb3+-doped fiber lasers have been attracted greatly because of its simple energystructure, no excited state absorption, and wide tunable range. They have great potential inthe field of industrial application, communication, military, as well as medical. However,there are now increasingly obtrusive thermal limits that need to be addressed for furtherpower-scaling of YDFLs. Thus, tandem pumping is proposed to solve the limitationproblems. Tandem pumping adopts1018nm fiber laser which at longer wavelength closer tothe laser wavelength instead of LD as the pump source. This thesis studied1018nm fiberlaser in theoretical, experimental and fiber fabrication aspect.In order to get high efficiency1018nm fiber laser, one of the effective methods is toregulate the fluorescence properties of fiber and make the emission sub-peak near1018nm.In this thesis, the mechanisms of how Yb3+ions fluorescence properties change in silicafiber were studied and1018nm ytterbium-doped fibers were obtained by co-doped method.Thus, we get the conclusion that Yb/P co-doped fiber is more suitable for1018nm fiber laser.Efficient1018nm fiber preform is made by MVCD combined with the solution technique.The emission sub-peak of the preform and fiber is at1008nm,1021nm respectively. Theemission sub-peak of the fiber is18nm shorter than normal Yb-doped fiber, and the emissiondifference at1018nm is2times larger. We also investigate and analysis fibers with differentcomponent.Based on rate equations of fiber laser, fiber parameter and laser structure parametereffect on short wavelength laser output are studied.1018nm fiber lasers with fibers of different parameters are also explored. Single-modelaser output with the22.8W at1018nm are achieved. The opto-optic efficiency is52.8%.The laser line-width is0.076nm. Consider the absorption pump only, the efficiency is62.5%.