一維漸進厚度變化之光子晶體研究

Abstract

本論文主要研究一維光子晶體中光子能隙如何擴大的特性。採用傳輸矩陣法和平面波展開法作模擬的工具。分別就兩種及三種材料的結構做探討，可以瞭解一維光子晶體的基礎特性。接著提出以無序的結構「漸變結構」來提高光子能隙寬度的方案，並藉由分析探討四種漸變結構可以得到幾個重要的結果。漸變結構一能夠大幅的提昇光子晶體能隙寬度高達400%左右。漸變結構四可得到一個在短波長處的狹窄通帶，穿透率可達40%，經過改變入射角發現可是透射率接近99%。漸變結構六可以也可以得到一個在短波長處的狹窄通帶，穿透率高達70%，經過改變入射角發現可是透射率接近99%。這是本文得到的嶄新的結果。

The main purpose in this thesis is to study how to broaden the photonic band gap in one dimensional photonic crystal. We use Transfer Matrix method and Plane Wave method as the tool to simulate the structures of two and three kinds of materials, we can understand the fundamental properties of the one dimensional photonic crystal. Then, we suggest using disorder structure, tapered structure, to broaden the photonic band gap and we can get few important results by analyze four kinds of tapered structure. When using tapered structure one, we can broaden the photonic band gap substantially by four hundred percent. When we use tapered structure four, we can get a narrow pass band at short wavelength region and its transmissivity is about forty percent. By changing incident angle, we can obtain the transmissivity of ninety-nine percent. Using tapered structure six can obtain the similar outcome, a narrow pass band with seventy percent transmissivity at short wavelength region, and we can also get the transmissivity of ninety-nine percent by changing the incident angle. It’s a brand-new result in the thesis.