臺灣博碩士論文加值系統

本論文利用多模態干涉於各向異性材料上之分光特性，以傾斜的次波長光柵結構來模擬等效於各向異性材料的雙折射，使用絕緣體上的矽晶體(silicon-on-insulator，SOI)建構出適合的多模態干涉長度達到有效的極化分光，並嘗試加入四種不同結構的鍺奈米條進一步縮短結構長度。最終使用嵌入式的鍺奈米條達到多模態干涉區的長度L_MMI縮短至66.94μm，同時維持損耗控制在〖IL〗^TM=-1.90，〖IL〗^TE=-1.08，並達分光〖ER〗^TM=11.92，〖ER〗^TE=11.20。

In this study we design a polarization beam splitter (PBS) based on anisotropy-engineered . To control over the birefringence and the anisotropy of the equivalent metamaterial , the SWG segments in the multimode region are tilted by an angle θ with respect to the transversal direction . With a silicon-on-insulator (SOI) platform, this PBS will have a smaller size combined with four types of structures using germanium nano-ribs . Finally, one of the proposed structure achieves a compact device , with the multimode region length L_MMI=66.94μm while maintaining 〖IL〗^TM=-1.90 〖IL〗^TE=-1.08 and 〖ER〗^TM=11.92 〖ER〗^TE=11.20.

目錄
摘要 i
Abstract ii
目錄 iii
圖目錄 iv
第一章 前言 1
1.1 緒論 1
第二章 基本原理 3
2.1 電磁波的性質 3
2.2 橫向模態(Transverse Mode) 4
2.3 極化分離器的品質 5
2.4 多模態干涉(Multi-mode Interfrence,MMI)[1] 6
2.5 次波長光柵(Sub-Wavelength Grathing,SWG)[3][4] 10
2.6 斜向次波長光柵(Tilted Subwavelength Grating,TSWG)[4][5] 13
2.7 輸出端口的Y型波導(Y-junction)[6] 16
第三章 TSWG極化分離器之設計與模擬 17
3.1 TSWG極化分離器結構[7] 17
3.2 TSWG加入鍺奈米條結構(Germanium nano-ribs)的四種結構 20
3.3 TSWG with Ge nano-rib結構A 22
3.4 TSWG with Ge nano-rib結構B 23
3.5 TSWG with Ge nano-rib結構C 24
3.6 TSWG with Ge nano-rib結構D 25
3.7 TSWG結構D的製造容忍度 27
第四章 結論 28
第五章 參考資料 29

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