本論文將設計一套Q切換摻鐿光纖雷射系統。並透過Matlab軟體來分析摻銩光纖的激發態³F₄能階用以Q切換摻鐿光纖雷射系統的可行度。架構中採用摻鐿的雙批層增益光纖後面接上摻銩的可飽和吸收體光纖，並透過模態場不匹配技術，藉以產生高功率的脈衝雷射，而架構中的器件除了激發源以外都能以光纖熔接機熔接而成，實現了精巧的全光纖脈衝雷射架構。論文中將藉由改變Q切換波長、幫浦功率、可飽和吸收體長度、共振腔長度等參數來進行討論，並透過銩原子各能階居量的探討，設法使Q切換效果達到最佳化。

This thesis will design a Q-switched ytterbium-doped fiber laser system. The feasibility of the Q-switched ytterbium-doped fiber laser system is analyzed by the Matlab software to analyze the excited state energy level of the doped fiber. The research structure uses ytterbium-doped dual-layer gain fiber followed by a saturable absorber fiber doped with ytterbium, and uses modal field mismatch technology to generate high-power pulsed laser. They can all be spliced with an optical fiber fusion splicer, realizing a compact all-fiber pulse laser architecture. In the paper, Matlab software will be used to discuss by changing the parameters of Q switching wavelength, pump power, saturable absorber length, resonant cavity length, etc., and through the discussion of the excited state energy level of the atom, try to achieve the Q switching effect optimize.

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