多層光柵結構週期性介電質波導

Multi-grating structures of dielectric waveguides

龔豊迪(Li-Ti Kung)

指導教授 ： 孫迺祥

義守大學/電機資訊學院/電機工程學系/碩士(2016年)

摘要

本論文針對多層多區介電質光柵波導結構，以Floqiet-Bloch理論作為理論分析之基礎，針對多區介電質光柵結構推導出其表示式求解波導之等效折射率，近而求取光柵結構在First Bragg與Second Bragg Condition的傳輸系數、反射系數與輻射損失等重要之物理特性。並且針對相異週期光柵結構、Liner結構、Oracle結構進行結構模擬與頻譜分析。模擬結果顯示，二階相異週期光柵組合結構可以成功等效出一階光柵週期對稱型結構之光柵特性，在共振區內無輻射能量散失，但在共振區外卻有輻射特性的特殊現象，並且其二階α值、3dB頻寬皆大於一階結構數據。Liner-a結構，成功模擬出光柵特性，證明此結構想法可以實際使用於業界，並且與相異光柵週期結構一樣特性，其二階α值、3dB頻寬皆大於一階結構數據。Liner-b結構，製做出的光柵特性與傳統光柵結構相異性不大。Liner-c結構，在二階布拉格光柵條件下，其效果等同於週期為Λ/2的兩個ㄧ階光柵週期結構組合。Oracle結構作為業界實際生產的產品，在分析其頻譜卻遇到的程式崩潰的問題，此次的程式無法改善此現象，程式後續需要繼續修改。

關鍵字

none

並列摘要

In this thesis, we use Floqiet-Bloch theory to analyze the gratings with Multi-grating sections. We develop a software to solve the effective index of periodic dielectric waveguides. The transmission, reflection and radiation spectrum of first Bragg and second Bragg condition of gratings are simulated. In addition, we focus on three grating structures: the combination structure of gratings, Liner structures and Oracle structures. The simulated results show that the second Bragg of the composited grating structures is similar to the first Bragg gratings, while the composited gratings have large attenuation constants and wide 3dB bandwidth. Moreover, we successful simulate three linear structures of gratings, where the properties of linear grating structures are similar to the composited grating structures. Finally, the properties of commercial Oracle structure are calculated.

並列關鍵字

none

參考文獻

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