基于ITO特性的亚波长表面等离子激元波导  

Sub-Wavelength Surface Plasmon Polariton Waveguide Based on ITO Characteristics

作　　者：王晓艳[1] 王燕[1] 秦雪[1] 阎晓娜[1] 张惠芳[1] 何英[1] 白丽华[1] 

机构地区：[1]上海大学理学院物理系,上海200444

出　　处：《激光与光电子学进展》2016年第5期256-262,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(11175045)

摘　　要：透明光学玻璃中的氧化铟锡(ITO)是一种高度简并的半导体,其介电常数随入射波长变化且为复数。以此作为介质层,设计了Ag-ITO-Ag波导结构,研究了其表面等离子激元(SPP)的相关特征参数及电磁波在该结构中的传输特性。具体给出了这种结构波导的场分布、SPP波长、传播距离及色散方程的表达式,讨论了其色散特性;研究了其群速度随入射波长的变化关系,讨论了介质层厚度对群速度的影响,以及相同的覆层结构(Ag)不同中心介质(ITO,air,SiO2)对群速度的影响及其慢光效应。结果表明,Ag-ITO-Ag波导结构更有利于光子器件的小型化和集成化。Indium tin oxide （ITO）, as a kind of transparent optic glass, is a highly degenerate semiconductor. The dielectric constant of ITO changes with incident wavelengths and is complex number. Ag-ITO-Ag waveguide is designed by ITO as dielectric layers. The transmission characteristics of electromagmetic waves in the structure of surface plasmon polariton （SPP） waveguide and the relevant characteristic parameters of SPP are obtained. In this structure, the expression of magnetic field distribution, SPP＇s wavelength, propagation distance and dispersion equation are derived and the dispersion characteristic is researched. Besides, the relationship between group velocity and incident wavelength is studied. The effects of the thickness of dielectric layer on group velocity, different core mediums （ITO, air, SiO2） of the structure with same cladding layers （Ag） on group velocity and slow light effect are discussed. The results show that the Ag-ITO-Ag waveguide structure is more favorable for miniaturization and integration of photonic devices.

关 键 词：表面光学 表面等离子激元 金属包覆介质波导 色散 群速度 

分 类 号：O436[机械工程—光学工程]