基于光子晶体的信道分插复用器设计.pdf

华中科技大学
硕士学位论文
基于光子晶体的信道分插复用器设计
姓名:冯志勇
申请学位级别:硕士
专业:光学工程
指导教师:孙军强
20060510
摘要
光子晶体是一种介电常数在空间周期变化的人造晶体,其具有类似于半导体中电
子带隙的“光子带隙”,如同在半导体中引入缺陷来控制电子的传播一样,在光子晶体
中引入缺陷能有效控制通过的光波的传输。正是由于光子晶体有着这样不同寻常的特
性,使得它在光通信和光计算领域有着广阔的应用前景,近些年来引起了人们的极大
关注,使得人们相信它就是光学领域中的“半导体”,光控制光的时代似乎就要来临。
本文的目的是设计一种基于光子晶体的信道分插复用器。文中首先概述了光子晶
体的概念及其特性,然后从麦克斯韦方程组出发,简要介绍了研究光子晶体的两种不
同方法,并分析了其优缺点,之后,利用平面波展开法分析了二维方形格子光子晶体
结构参数对带隙大小的影响,据此选取了一种特定结构的二维方形格子光子晶体作为
器件设计平台,而后,分别分析了此光子晶体中的点缺陷和线缺陷,研究了各自的模
式特性和能带特性,并且利用紧束缚法和时域耦合模理论对它们间的耦合相互作用做
了详细的分析,最后,根据目前光子晶体信道分插复用器的发展状况,结合文中的研
究结果,提出了一种带有对称全反射壁的光子晶体信道分插复用器,根据时域耦合模
理论建立了这种器件的理论模型,并做了相应分析,同时,利用时域有限差分法模拟
了器件在脉冲态和稳态下的工作状况,并与理论模型的结果做了比较分析。

关键词:光子晶体光子带隙缺陷平面波展开
时域有限差分耦合模理论










I
Abstract
Photonic crystals which have as the electric bandgap in semiconductors photonic
bandgap are artificial structures in which the dielectric constant changes periodically. By
introducing defects light can be efficiently controlled like the control of electronics in
semiconductors. It is the distinct characteristics of photonic bandgap that have inspired great
interests recent years and make people believe it is the semiconductors in optics. It seems
that the time of controlling light by light ing.
Our purpose is a design of channel add/drop filters based on photonic crystals. First, the
concept and characteristics of photonic crystals are introduced. Then from the Maxwell
equations, two different methods solving problems involving photonic crystals are briefly
introduced. The PWE method is used to analyze how structure parameters of photonic
crystal affect the width of photonic band gap. And choose 2D square photonic crystal of
special structure as the design platform. Then, different defect states and the coupling
between them in this photonic crystal are investigated. Ultimately, a photonic crystal channel
add/drop filter with symmetric 100% reflectors is proposed according to the results studied