Accurate Modeling of Dark-Field Scattering Spectra of Plasmonic Nano structures
Accurate Modeling of Dark-Field Scattering Spectra of Plasmonic Nano structures
复制标题
等离激元纳米结构暗场散射光谱的精确建模。
DOI：
10.1021/acsnano.5b03622
复制
发表时间：
2015-10-01
期刊：
影响因子：
17.1
通讯作者：
Shen, Zexiang
中科院分区：
文献类型：
--
作者：
Jiang, Liyong;Yin, Tingting;Shen, Zexiang
暗场显微镜是一种广泛使用的测量等离子体纳米结构的光学共振的工具。然而，目前用于模拟暗场散射光谱的数值方法是在平面波照明下进行的，无论是垂直入射还是从一个方向倾斜入射。在实际实验中，光通过一个环形圈在一定的掠射角范围内聚焦到样品上。在本文中，我们提出了一个理论模型，能够准确地模拟暗场光源与环形圈。模拟正确地再现了直径超过140 nm的金纳米盘的散射光谱中的违反直觉的蓝移。我们相信，我们提出的模拟方法可以作为一个通用的工具，能够模拟暗场散射光谱的等离子体纳米结构以及其他介电纳米结构的尺寸超出准静态限制。
Dark-field microscopy is a widely used tool for measuring the optical resonance of plasmonic nanostructures. However, current numerical methods for simulating the dark-field scattering spectra were carried out with plane wave illumination either at normal incidence or at an oblique angle from one direction. In actual experiments, light is focused onto the sample through an annular ring within a range of glancing angles. In this paper, we present a theoretical model capable of accurately simulating the dark-field light source with an annular ring. Simulations correctly reproduce a counterintuitive blue shift in the scattering spectra from gold nanodisks with a diameter beyond 140 nm. We believe that our proposed simulation method can be potentially applied as a general tool capable of simulating the dark-field scattering spectra of plasmonic nanostructures as well as other dielectric nanostructures with sizes beyond the quasi-static limit.