本論文將研製一高功率輸出的短脈衝雷射，可望用於高精密加工、雷射切割、醫療美容雷射、微創手術，甚至是軍事照明運用等。為達成此目的，本文架設一被動式偏振疊加波鎖模架構來產生鎖模雷射，並透過不同的架構元件修改來找出輸出表現最佳的架構，當泵激雷射電流操作在200 mA下，並透過耦合分光器之分光比的參數調整後可得到最寬之頻寬輸出，3 dB頻譜寬度為10.08 nm，且脈衝雷射的中心波長約在1560 nm附近，屬於C-Band波段，接著透過共振腔長度調整，建構出三種不同規格的脈衝雷射，其脈衝寬度約為5 ns、20 ns與400 ns，利用平均功率與重複率大小可計算出脈衝能量分別為2.34、3.98與86.2 nJ。
然而脈衝之平均輸出功率不足以滿足目標需求，因此本文將設計高功率鉺鐿共摻光纖放大器來提升脈衝之平均功率，並針對高功率放大器的增益介質長度進行優化以達到最佳增益，同時分析前向與後向泵激架構，最後由於雜訊指數及脈衝尖峰功率過大等考量，選擇前向泵激架構來繼續後續實驗，在放大器泵激光源電流操作在3 A之下，可使最佳增益達到28.36 dB。
最終本論文將上述所提出之被動式偏振疊加波鎖模當作種子雷射，藉由高功率鉺鐿共摻光纖放大器來提升整體之平均輸出功率，最後當三種規格的短脈衝雷射之平均功率為13.02、13.27與15.67 mW且放大器泵激光源操作於7 A時，能得到放大後之平均輸出功率分別為2041.74、2018.37與2084.49 mW且經過放大器後之脈衝表現並不會有明顯畸變，有效地將脈衝能量提升為367.22 nJ、606.11 nJ與11.46 μJ，將輸入放大器前後數據比較後，三種共振腔長度的脈衝能量依序放大了約157、152和133倍。

In this thesis, we develop a high-power and short-pulsed laser and we expect to use it in the applications of high-precision machining, laser cutting, medical beauty, minimally invasive surgery and military lighting. In order to achieve this objective, the passively mode-locked laser was built up by using the polarization additive-pulse mode-locking (APM) mechanism. Different structures and elements were designed and used to find a better configuration. Under 200 mW driving current, the widest bandwidth output is obtained by adjusting the splitting ratio of the splitter; while the 3 dB bandwidth is 10.08 nm and the center wavelength of the pulsed laser, which belongs to the C-Band, is about 1560 nm. Through the adjustment of resonant cavity length, we can find the construction of three different specifications of the pulsed laser; while the pulse width is about 5 ns, 20 ns and 400 ns. Moreover, we use the average power and the repetition rate to calculate that the pulse energy is 2.34 nJ, 3.98 nJ and 86.2 nJ, respectively.
However, the average output power of the pulsed laser isn’t sufficient to meet the target requirements, so we design a high-power Erbium/Ytterbim co-doped fiber amplifier (EYDFA) to enhance the average power of the pulse. We also optimize for the gain fiber length of the high power amplifier to achieve the optimum gain while analyzing the forward and backward of pumping architectures. To consider that the noise figure and the peak power of the pulse is too large, we decide to select the forward pump architecture to continue the follow-up experiment. At 3A driving current for pumped laser diode, the maximum gain is 28.36 dB for the EYDFA in 0 dBm launched laser.
Finally, the passively polarization APM laser as mentioned above was acted as a seed laser and was amplified by an Erbium/Ytterbim co-doped fiber amplifier. When the average power of the three standard short-pulsed lasers are 13.02 mW, 13.27 mW and 15.67 mW, as well as the amplifier pump laser source is operated at 7 A, the average output power can be obtained to be 2041.74 mW, 2018.37 mW and 2084.49 mW. The performance of the pulse through the amplifier do not have significant distortion, while the pulse energy is effectively promoted to 367.22 nJ, 606.11 nJ and 11.46 μJ. After the comparison of the data, the pulse energy of the three resonant cavity lengths is approximately amplified by 157, 152 and 133 times, respectively.

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