本論文重點為利用高功率泵浦系統研製穩定的1590-nm全光纖被動式Q切換脈衝雷射，並藉由實驗及模擬驗證高功率泵浦不適用在單共振腔之Q切換雷射架構，必須加入第二共振腔才能製作穩定Q切換序列脈衝雷射。在雙共振腔雷射系統中，藉著Q切換及增益切換自我平衡機制，形成穩定的Q切換序列脈衝雷射。增益介質採用鉺鐿共摻增益光纖，避免鉺離子高摻雜導致雷射效率降低，同時提高增益介質吸收能力，取得更佳的脈衝特性，可飽和吸收體選用摻銩光纖，在1590 nm波段下，銩元素的吸收截面積大於鉺元素的放射截面積，容易形成Q切換脈衝雷射。想藉由模態場面積不匹配技術改善脈衝特性，卻因為所造成的損耗太大及高摻雜光纖造成高能態離子被激發，可飽和吸收體回復量減少，使得脈衝特性反而變得更差，最後製作出在11.92 W泵浦下脈衝寬度為370 ns、脈衝能量為41.47 µJ、脈衝峰值為112 W、脈衝重覆率為33.76 kHz的穩定Q切換序列脈衝雷射。最後模擬共振腔內參數對脈衝特性的影響，提供未來改善此雷射架構的方向。

The purpose of this thesis is to demonstrate a stable and high-performance 1590-nm passively Q-switched all-fiber laser using a high-power cladding-pumping system, and we verify that high pump power is not suitable for the single resonant Q-switched laser system by experiments and simulations. There must be double resonators in the Q-switched laser system if we want high output power. In a laser system with double resonators, a stable Q-switched sequential pulse is formed by the Q-switching and gain-switching self-balanced mechanism. Using Er-Yb co-doped gain fiber can avoid the clustering effect caused by high doping concentration of Er, and raise the absorption strength of the gain fiber at the same time. We want to improve the pulse characteristics by the mode-field-area(MFA) mismatch, but the pulse characteristics become worse because of the loss caused by MFA mismatch and the population of higher-order states excited because of the highly doped fiber. Finally, we made a stable Q-switched sequential pulse laser under the 11.92 W pump power with a width of 370 ns, a pulse energy of 41.47 μJ, a pulse peak power of 112 W, and a pulse repetition rate of 33.76 kHz and simulated the effect of changing parameters in the resonators on the pulse characteristics to provide a direction for improving this laser system in the future.

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