本論文致力於研究將絕熱工程(Adiabaticity Engineering)沿伸運用於設計光波導結構，藉由重新定義絕熱工程中的絕熱路徑對波導寬度變化率，以得到新設計之波導結構與絕熱參數，使得模態在波導中傳輸，能量不會被激發至其他模態，使波導沿傳播方向保持其絕熱性。
在光子積體電路中，透過利用極化分光器(polarization beam splitters)與極化旋轉器(polarization rotators)分別處理不同偏振態的光訊號來改善絕緣層覆矽結構(silicon-on-insulator, SOI)波導對光偏振太敏感之限制，而元件會衍伸出增加積體光路尺寸與損耗等問題，因此擁有偏振獨立特性的元件逐漸受到重視。
根據3-dB分光器基於絕緣層覆矽條狀波導(strip waveguide)設計與模擬結果，利用絕熱工程理論可以將元件耦合長度縮短至28.151μm、50.928μm，不僅大幅縮短了傳統線性分光器耦合長度91.406μm，且同時保有良好的頻寬與製程容忍度。在頻寬200nm(波長1450nm~1650nm)下的分光輸出差保持在1.03dB下，元件製程容忍度在±20nm的範圍中分光輸出差保持在0.85dB下。

We present a short and broadband polarization-independent 3-dB coupler based on silicon-on-insulator (SOI) waveguide. By engineering the adiabaticity distribution using a single control parameter, we obtain shortcuts to adiabaticity in optical waveguides for multimode systems. Our simulations show that the shortest coupler can be achieved at 28.151μm and 50.928 μm, the devices have high tolerance to fabrication errors, a low excess loss < 1dB, and the bandwidth is even as large as 200nm (from 1450 to 1650nm) with an imbalance of less than 1.03dB.

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