空间相干性对电解质纳米二聚体散射特性的影响  

Effect of Spatial Coherence on the Scattering Properties of a Dielectric Nanodimer

作　　者：何颖君 陶磊明 薛鹏 

机构地区：[1]广东石油化工学院理学院,广东 茂名

出　　处：《现代物理》2023年第6期163-170,共8页Modern Physics

摘　　要：本文研究一个电介质纳米二聚体在部分相干光激发下的散射特性。首先解析推导了该二聚体的耦合电偶极子模型,并计算了散射光的远场强度分布特性。我们发现入射光的空间相干性对该纳米结构的散射强度、散射分布图样、散射方向性等都有显著影响。我们的计算结果尤其表明,入射光的空间相干性与它的偏振态和波长之间会产生复杂的相互作用从而改变上述散射性质。进一步通过调节空间相干度的幅值和相位,实现了对二聚体散射的强度方向性调控,这在不考虑磁多极激发的情况下是较为罕见的。我们的研究方法和结果对于进一步开发纳米结构的散射功能具有潜在的价值。In this article we studied the scattering properties of a dielectric nanodimer excited by a partially coherent incident light. Far-field distributions of the intensity of scattered light were analyzed through both analytical derivations and numerical computations with the coupled electric dipole model. We found prominent effects of spatial coherence on the scattering strength, the scattering pattern and the scattering directivity. In particular, our computational results demonstrated com-plex interplays between the spatial coherence and the polarization and wavelength of incident light. Through tuning both the norm and phase of the degree of spatial coherence, we achieved evident transverse and directional scattering which were otherwise impossible without magnetic excitations. Our methods and findings in this study would be helpful in exploiting scattering functionalities using nanostructures.

关 键 词：纳米二聚体 散射 电偶极子 空间相干性 

分 类 号：O43[机械工程—光学工程]