Theory And Numerical Analysis Of Multi-point Pump Double-clad Fiber Lasers

Benefit from the particular structure of the double-clad fibers (DCF) and the excellent performance of Yb3+, double-clad fiber lasers (DCFLs) are being developed rapidly these years. Firstly, the pump light coupling technology is introduced in this paper, and the developing situation is summarized, furthermore, the output performance of multi-point pump DCFLs is researched deeply. The research work primarily concludes as follows:1. The steady rate equations are get under the analysis of four energy class of Yb3+, and the approximate resolution is carried out.2. The new numerical resolution is get under the analysis of the physics problem. Among them, the end-pump arithmetic has fast resolution velocity, and the multi-point pump arithmetic has high reliability.3. Some problems of multi-point pump are researched deeply, and depend on this some useful conclusions are get to optimize the design of DCFLs.4. The loss of the pump points is took into account for the fist time in this paper, the limitation of multi-point pump is put forward.5. The thermal effect is studied as well in this dissertation, particularly, the temperature distribution along fiber under multi-point pump is brought forward, and the improvement of thermal effect under multi-point pump is researched as well.6. Upon the analysis of the output performance and the thermal effect of DCFLs, the processes of the DCFLs design are brought forward.To sum it up, some optimization methods of the DCFLs design are gained in this dissertation, and all these methods can conduct the experiment of DCFLs.