学校代码:10246学号:061019034博士学位论文二维蜂窝光子晶体边缘态的色散及效应研究院系:物理学系专业:凝聚态物理姓名:欧阳纯方指导教师:资剑完成日期:2011年5月20日指导小组成员名单资剑教授刘晓晗副教授胡新华研究员目录摘要............................................................................................................................................iiAbstract.......................................................................................................................................iii第一章光子晶体表面态简介.....................................................................................................11.1从电子晶体到光子晶体.............................................................................................21.2光子晶体表面态.........................................................................................................91.3金属表面等离子体激元...........................................................................................21参考文献............................................................................................................................28第二章理论计算方法简介......................................................................................................352.1平面波展开方法.......................................................................................................352.2有限差分时域方法...................................................................................................362.3传输矩阵方法............................................................................................................38参考文献............................................................................................................................41第三章蜂窝光子晶体边缘态..................................................................................................423.1从石墨烯到光子石墨烯...........................................................................................423.2蜂窝光子晶体边缘态...............................................................................................513.3边缘态波导................................................................................................................593.4打孔体系的边缘态...................................................................................................65参考文献............................................................................................................................67第四章蜂窝光子晶体边缘态的彩虹效应.............................................................................714.1金属光栅的彩虹效应...............................................................................................724.2边缘态分频器............................................................................................................804.3边缘态的彩虹效应...................................................................................................83参考文献............................................................................................................................92第五章蜂窝光子晶体边缘态的慢光应用.............................................................................955.1光子晶体慢光波导...................................................................................................965.2边缘态慢光波导.....................................................................................................103参考文献..........................................................................................................................109结语........................................................................................................................................113发表论文....................................................................................................................................114致谢........................................................................................................................................115i摘要石墨烯(Graphene)是只有一个原子层厚度的二维晶体,具有完美的晶体结构和不同寻常的电子态性质。有限尺寸的石墨烯带存在边缘态,显示出有趣而丰富的电子和自旋输运性质。边缘态也存在光子体系中,如光子晶体和等离子体晶体。本文主要研究与石墨烯具有相同对称性的二维蜂窝光子晶体(Honeycombphotoniccrystals)边缘态的色散和性质。边缘态是一种局域在光子晶体-介质界面并向光子晶体和介质内部指数衰减的电磁波。蜂窝光子晶体边缘态具有低维度、高局域、亚波长的特点。改变边界格点的参数,可以方便地调节边缘态的色散。基于边缘态亚波长局域和连续可调的性质,我们研究了蜂窝光子晶体边缘态波导的慢光效应。本论文作者力求与读者讨论以下几个问题:1、什么是光子晶体边缘态?2、我们为什么要研究蜂窝光子晶体,其边缘态有什么特殊的地方?3、蜂窝光子晶体边缘态有哪些潜在的应用?因此本论文内容将如下安排:第一章简要介绍光子晶体和光子微纳结构中两类重要的表面波:介质光子晶体表面态和金属-介质表面等离子体激元。包括基本概念、性质和研究进展。第二章简要介绍研究光子晶体边缘态用到的计算方法:平面波展开法、有限差分时域法和传输矩阵法。第三章从介绍石墨烯开始,回答为什么要研究蜂窝光子晶体的问题。分析蜂窝光子晶体的对称性对能带的影响,狄拉克点附近光子的输运性质。重点讨论蜂窝光子晶体zigzag边界边缘态亚波长局域和色散连续可调的性质。我们设计了边缘态波导和高转弯效率的波导转弯器,在器件小型化和集成光路领域具有优势。在第四章和第五章,我们研究蜂窝光子晶体边缘态在光子晶体慢光领域的潜在应用,包括彩虹效应和零色散慢光效应。利用色散连续可调的性质,设计了渐变边缘态波导,使不同频率的光停留在不同位置即彩虹效应。边缘态正弦型色散曲线,有效地抑制了高阶色散实现了零色散慢光。关键词:光子晶体表面态,蜂窝光子晶体,边缘态,彩虹效应,慢光中图分类号:O469iiAbstractGraphene,asinglelayerofgraphite,hasattractedmuchattentionowingtoitsperfect2Dstructureandunusualelectronicproperties.Withthepresenceofaboundarygraphenehasedgestatesresultingininterestingtransportpropertiesofchargeandspin.Ontheotherhand,edgestatesmayalsobepresentinphotonicsystemssuchasphotoniccrystals(PCs)andplasmoniclatticeswithinterestingopticalproperties.Thisthesisfocusesontheinvestigationsofedgestatesontheboundariesofhoneycombphotoniccrystals(HC-PCs),whichisthephoton