回饋式光參數放大器波導擁有相當多的優點，例如經由波導的方式，大幅提升波長轉換的效率；利用分佈式回饋來得到單一頻率的輸出；準相位匹配的使用則可以產生任意波長的雷射；光學元件的使用量大幅減少也增加了系統的穩定度和可靠性；不再需要依靠精細的人工微調光路也是一大特點；波導的使用也方便和積體光學的被動元件做進一步的結合。相較於一般的波長轉換系統約需50cm x 50cm 的地方放置，本設計搭配一般半導體雷射則只約佔10cm x 10 cm的大小。 (若不包括半導體雷射的電源)
在本論文裡，我們首先推導了基本的回饋式光參數放大波導的理論。相較於一般波長轉換的裝置多需要千瓦的功率(脈衝式)，經由一些合理的參數假設 我們計算出本放大器輸入的最低功率為100毫瓦。波導的高轉換效率和分布回饋式的設計大幅地降低了本放大器對於最低輸入功率的要求。第三章探討此類高效率波長轉換的波導製作，第四章則比較各式各樣的分佈回饋式的格柵製作，這裡格柵的週期約為1.03微米。實際在鋰酸鋰晶體製作格柵非常困難，即便使用乾蝕刻的方式也無法製作出良好品質的短週期格柵，在此我們在進行乾蝕刻之前先進行短時間的質子交換，利用此製程，增加晶體內的應力，使得蝕刻的速度大幅增加。對於一個週期為2微米的格柵，我們能製作的最大深度為 0.6微米。雖然質子交換會降低波長轉換的效率和增加波導的耗損，經由程式的模擬 在如此的質子交換參數之下，約還能保持95%以上的波長轉換效率。經由量測穿透光對應於不同的入射波長，我們成功的量測到約9%穿透光的降低，峰值波長為1529.18奈米，半高全寬為 0.0189奈米，據推算出的回饋參數為每公分0.1，由此回饋式格柵的幾何形狀所計算而得的回饋參數為每公分0.6。低於理論值的主要原因為，波導的端面必須有非常良好的抗反射光學膜，否則此格柵回饋的力度會大幅降低。此外受限於黃光設備的關係，整體的回饋式格柵的製作並不夠完美。相信只要能克服這兩點，對於一個擁有超低功率輸入需求、單一波長輸出、 任意波長轉換的元件來說，必將成為非常重要的積體光學元件之一。

The Distributed Feedback Parametric Oscillator built in APE PPLN waveguide is characterized as a high efficient, arbitrary single frequency generation, and compact device. Theory of DFB OPO waveguide is derived and the calculated threshold is around 0.1W for . We assume the length of the DFB grating is the same with the PPLN, which is 4cm long. The parametric process involves 800nm pumping laser and the signal wavelength is 1530nm (also be the Bragg wavelength). The threshold is 40 times lower if we compare DFB OPO for bulk and waveguide. The major achievement of this dissertation is the development of the distributed feedback grating on the annealed proton exchange waveguide. Modeling and optimizing of the DFB grating is given. Around 9% transmission drop at 1529.18nm with FWHM 0.0189nm is measured. The fitted DFB coupling strength is 0.1/cm while the theoretical value is 0.6 /cm. The imperfect lithography grating and the end facets reflection lower the effective feedback strength. The Quasi Phase Matching technique is used for frequency conversion process. In the near future, a good quality DFB grating would be fabricated with high reflectivity and narrow bandwidth; DFB OPO waveguide could be demonstrated and explored.

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