拓扑绝缘体和手征介质界面的Goos-Hnchen位移和Imbert-Fedorov位移  

Goos-Hnchen and Imbert-Fedorov Displacements across the Interface of Topological Insulator and Chiral Metamaterials

作　　者：唐龙 曾然[1,2] 李齐良 毕美华[1] 杨国伟[1] 羊亚平[2] TANG Long;ZENG Ran;LI Qi-liang;BI Mei-hua;YANG Guo-wei;YANG Ya-ping(School of Communication Engineering,Hangzhou Dianzi University,Hangzhou 310018,China;MOE Key Laboratory of Advanced Micro-Structured Materials,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]杭州电子科技大学通信工程学院,杭州310018 [2]同济大学物理科学与工程学院先进微结构材料教育部重点实验室,上海200092

出　　处：《光子学报》2018年第8期177-184,共8页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.11574068,61501157)和浙江省自然科学基金(No.LQ16F050004)资助

摘　　要：研究了线极化波在拓扑绝缘体和手征介质分界面上全反射时的Goos-Hnchen(GH)侧向位移和Imbert-Fedorov(IF)横向位移特性.使用修正的能流法推导出各位移表达式,数值计算分析了入射角、拓扑磁电耦合效应、手征性等对位移的影响.结果表明,当TE波入射时,拓扑绝缘体的磁电耦合效应或手征介质的手征性对两种位移的影响较为一致,即拓扑磁电耦合对GH和IF位移均为抑制,手征性对位移基本为单调增强或单调抑制.而TM波入射时,拓扑磁电极化率会使位移先增大后减小,位移存在一个极值,手征参数的增大使该极值向拓扑磁电极化率较小值方向移动;手征参数对位移的影响虽基本上是单调性的,但在某些情况中较为特殊,如右旋圆极化波的GH位移在拓扑磁电极化率对位移增强阶段,手征性也将增强位移,而在拓扑磁电极化率对位移抑制阶段,手征性也同时抑制位移.对拓扑绝缘体和手征介质界面GH和IF位移的研究,为测量拓扑磁电耦合特性及手征电磁交叉极化性质提供了一种光学方法.The Goos-Hanchen（GH） lateral displacement and Imbert-Fedorov（IF） transverse displacement of a linear polarized wave at the interface of topological insulator and chiral metamaterial was investigated. Based on the modified energy flux method, the expressions of the spatial shifts were derived, and the relations between the shifts and the incident angle, topological magnetoelectric coupling effect, chiral parameter were also numerically discussed. It is found that, for a linear polarized TE beam, the magnetoelectric couplin effect of the topological insulator or the chirality of the chiral medium has consistent influence on both the two shifts, that is, the topological magnetoelectric coupling can generally suppress both the GH and IF shifts, and the chirality may monotonously enhance or suppress both the two shifts. When gradually enhancing the topological magnetoelectric polarizability, the GH and IF shifts of the linear polarized TM incident wave will be firstly increased, and then it will be suppressed. There exists an extreme displacement. The increase of chiral parameters makes this extreme displacement move towards the smaller value of the magnetoelectric polarizabilityl Although the influence of chiral parameters on the shifts is generally monotonic, but it is special in certain cases, for example, in case of the GH shift of a right-handed circularly polarized wave, during the period when the topological magnetoelectric coupling increases the shifts, the chirality will also show the enhancement, while in the stage of shift suppression by topological effect, the chirality may suppress the shifts in the meantime. The research on the GH and IF shifts at the interface of topological insulator and chiral metamaterials may develop a new way to control the GH and IF shifts. It also provides an optical method for measuring the topological magnetoelectric coupling and chiral electromagnetic cross-polarization.

关 键 词：拓扑绝缘体 手征介质 GOOS-HANCHEN位移 Imbert-Fedorov位移 全反射 

分 类 号：O436[机械工程—光学工程]