在積體光路的設計與運作中，極化的特性限制了整個光學系統的運作，一個常用的解決方法，就是藉由極化分集系統來固定系統內的極化模態。其中極化分光器是構成極化分集系統中的一個重要的元件。本論文以 SOI 結構為基礎，設計極化分光器，並以縮小元件尺寸與增加元件操作頻寬為研究方向，以促進高密度積體光路的發展。
為了分析所設計的極化分光器，本論文使用三維有限差分時域法進行數值模擬分析，並整合非對稱型定向耦合器及漸變式波導結構形成極化分光器。首先，對於非對稱型定向耦合器，我們利用兩條非對稱直波導，將其設計成只有TE極化態可以耦合，藉由適當調整兩條波導的長度，使其所包含的能量相等，再加入漸變式的波導結構，成功的完成極化分光器的設計。為了改進極化分光器的長度與頻寬，我們對於低波導的後半段，選擇與高波導產生一個位移，分別考慮初始間距為 0.1

Polarization dependences of optical devices in highly-integrated optical systems become a major problem. To overcome this issue, one can implement polarization diversity scheme to achieve a single polarization on-chip network. One of the essential components in a polarization diversity scheme is the polarization beam splitter (PBS). In this thesis, we will a PBS based on a silicon-on-insulator (SOI) platform with reduced device size and broad operation bandwidth.
We use the three-dimensional Finite-Difference Time-Domain (3D-FDTD) method to perform the simulation. First, we use two asymmetric waveguides to design an asymmetric directional coupler with only TE-like mode phase matching condition. We then tape the lower waveguide to keep the TE-polarized light, and split the TE- and TM- polarized light. By utilizing an asymmetrical directional coupler with a tapered waveguide, we have achieved a 7.3

摘要i
英文摘要ii
目錄iii
圖目錄iv
表目錄viii
第一章 簡介1
1.1 絕緣層上鍍矽 2
1.2 極化分集系統 3
1.2.1 極化分光器 4
1.2.2 極化旋轉器 6
1.3 研究動機 8
第二章 數值模擬與分析方法11
2.1 波束傳播法11
2.2 有限差分時域法16
第三章 SOI 基本波導模擬與分析21
3.1 模態耦合理論 21
3.2 基本波導特性 27
第四章 極化分光器元件設計及分析36
4.1 非對稱型定向耦合器36
4.2 極化分光器41
第五章 結論與未來展望59
參考文獻60

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