具石墨烯層Fabry-Perot結構之光傳輸特性

Abstract

本論文主要目的在於研究具石墨烯層Fabry-Perot結構的光傳輸特性，兩邊為對稱的雙介電多層結構，也就是光子晶體結構，首先介紹石墨烯的光學特性，說明馬克士威方程式、赫姆霍茲方程式、波印廷理論等研究會需要用到的電磁波理論。接著探討電磁波在石墨烯與介電質之多層結構的傳遞行為，並推導其轉移矩陣及色散方程式。然後模擬兩種不同結構分別是傳統Fabry-Perot結構與具石墨烯層Fabry-Perot結構，藉由改變週期層數、空腔相位、石墨烯的化學位能，來觀察其光傳輸特性的變化，研究結果顯示反射率、穿透率、吸收率會隨著空腔相位、週期層數、化學位能變化，不同結構的變化趨勢不同，可藉此製作需要的光學元件，可應用於可調性的濾波器和光學開關上。

The main purpose of this thesis is to analyze the light propagation in Fabry-Perot resonator with graphene sheet. First, the optical properties of graphene and the theories about electromagnetic waves such as Maxwell’s equations, Helmholtz equation and Poynting’s theorem are briefly introduced. Second, the analysis of the light propagation in dielectric-graphene multilayer structures using transfer-matrix method is derived. Finally, by analyzing Fabry-Perot resonator with graphene sheet, the result turns out that the reflection, transmission, absorption are sensitive to the thickness of cavity, the period number of structure and the chemical potential of graphene. According to the results, this structure can be applied to a variety of electro-optic devices such as tunable filter or light switching.