不对称纳米环/椭球二聚体的高阶表面等离激元共振特性  

Properties of High Order Surface Plasmonic Resonance in Asymmetry Nanoring/Ellipsoid Dimer

作　　者：王兆华[1] 杨健[1] 任立庆[1] 王憨鹰[1] WANG Zhao-hua;YANG Jian;REN Li-qing;WANG Han-ying(College of Energy Engineering,Yulin University,Yulin 719000,China)

机构地区：[1]榆林学院能源工程学院

出　　处：《科学技术与工程》2019年第15期20-23,共4页Science Technology and Engineering

基　　金：地区科学基金(51861034);陕西省科学技术厅项目(2014K05-11)资助

摘　　要：基于三维有限元法,研究了不对称纳米环/椭球二聚体的表面等离激元共振和局域场增强光学特性。结果可得可调的高阶表面等离激元共振,这样的高阶共振源于纳米环和纳米椭球之间的等离激元耦合。同时,在两个纳米结构耦合下,在纳米椭球上可以观察到环形电流,其产生了增强的局域电磁场。数值模拟结果表明,纳米环/椭球二聚体的偏心方向和偏心率对表面等离激元共振有着重要的影响。此结果在表面增强光谱学和生物传感方面都有着潜在的应用。Surface plasmonic resonance and near-field enhancement in asymmetry nanoring/ellipsoid dimer( ANRED) are investigated theoretically using the three-dimensions finite-element method. Tunable surface plasmonic resonance of high-order is achieved. It is shown that such high-order resonances result from the plasmonic coupling between the bright mode of the nano-ellipsoid and the dark mode of the asymmetry nanoring. Interestingly,a current loop is observed on the nano-ellipsoid under the coupling of two nanostructures,producing enhanced local fields. The simulations show that the eccentric direction and eccentricity of ANRED have an important influence on the surface plasmonic resonance. This method might find applications in surface-enhanced spectroscopy and biosensing.

关 键 词：表面等离激元共振 局域场增强 不对称纳米环/椭球二聚体 偏心方向 

分 类 号：O433.5[机械工程—光学工程]