V形硅纳米球团簇的多极散射分析  

Multipole Scattering Analysis of a V-shaped Cluster of Silicon Nano-spheres

作　　者：何颖君[1] 杨俊桦 陈丽芳 陈星源[1] 徐祥福[1] 赖国霞[1] HE Yingjun;YANG Junhua;CHEN Lifang;CHEN Xingyuan;XU Xiangfu;LAI Guoxia(Guangdong University of Petrochemical'Technology,Maoming 525000,Guangdong China)

机构地区：[1]广东石油化工学院,广东茂名525000

出　　处：《河南科学》2021年第5期710-714,共5页Henan Science

基　　金：国家自然科学基金项目(12074441);广东省自然科学基金-粤东西北创新人才联合培养项目(2016A030307026);茂名市科技计划(工业攻关类)项目(201617)。

摘　　要：针对高折射率纳米粒子内部可激发起丰富的米共振,对由五个硅纳米粒子组成的V形小簇散射光的远场分布进行了研究.基于多极子理论对表征散射特性的主要参数的计算方法进行了分析,利用数值方法求得了全空间的散射场分布,代入多极子散射公式中得到了多极子系数、散射截面、散射方向性等主要参数.研究结果表明,该结构可以实现与单球类似的明显方向散射之外,其自身的电偶极、电四极辐射随波长分布与单粒子有显著的不同.而散射的远场特征可以使用多极子系数的光谱分布以及它们之间的干涉效应给予解释.研究结果在操控较复杂纳米结构光学特性方面有潜在的应用价值.Intense research interest are recently attracted to the scattering properties of high refractive-index dielectric nano-particles,due to the Mie-resonance excited inside such structure.In the present paper,we studied the far-field distribution of scattered light from a V-shaped small cluster formed by five silicon nano-spheres.We firstly analyzed the computation methods of the main parameters characterizing the scattering behaviors using multipole radiation analysis.Then we numerically computed the scattered fields in the whole space and substituted the results into the multipole scattering formula to obtain the multipole coefficients,the scattering cross-section and the scattering directivity.The results show that the structure can realize obvious directional scattering similar to that of a single particle,and its own electric dipolar and electric quadrupolar radiation with wavelength distribution are significantly different from that of a single particle.The far-field characteristics of the scattering can be physically explained by the spectral distribution of the multipole coefficients and the interference effect between them.Our study have potential applications in light field manipulation through rather complex nano-structures.

关 键 词：纳米粒子 米散射 米共振 多极子 散射截面 方向性 

分 类 号：O436.2[机械工程—光学工程]