Raman scattering images and spectra of gold ring arrays
Raman scattering images and spectra of gold ring arrays
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DOI：
10.1103/physrevb.73.245417
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发表时间：
2006-06
影响因子：
3.7
通讯作者：
G. Laurent;N. Félidj;J. Grand;J. Aubard;G. Lévi;A. Hohenau;F. Aussenegg;J. Krenn
中科院分区：
文献类型：
--
作者：
G. Laurent;N. Félidj;J. Grand;J. Aubard;G. Lévi;A. Hohenau;F. Aussenegg;J. Krenn
我们通过结合消光光谱、表面增强拉曼散射 SERS 光谱和两种变体的显微暗场成像来分析 m 尺寸的金纳米粒子环的光学性质。成像过程依赖于纳米颗粒上吸附的亚甲基蓝染料分子的 SERS 或弹性散射光。弹性散射光图像由颗粒散射光的相干性和强度控制，而 SERS 图像反映了颗粒在对应于显微镜点扩散函数的表面区域上非相干平均的光学近场。通过对消光光谱、散射光和SERS图像的分析，我们发现环中单个金纳米粒子的近场相互作用起着次要作用。通过简单的模型计算可以很好地再现散射光和 SERS 图像。由于不同的信号生成和相干特性，两种成像方法的结合是表征纳米结构金属表面光学特性的有用手段。
We analyze the optical properties of m-sized rings of gold nanoparticles by the combination of extinction spectroscopy, surface enhanced Raman scattering SERS spectroscopy and microscopic dark field imaging in two variants. The imaging process relies on either SERS from methylene blue dye molecules adsorbed on the nanoparticles or elastically scattered light. Whereas elastically scattered light images are governed by the coherence and intensity of the light scattered from the particles, SERS images reflect the optical near field of the particles averaged incoherently over a surface area corresponding to the point spread function of the microscope. From the analysis of the extinction spectra, scattered light and SERS images, we find that near field interaction of the single gold nanoparticles in the rings plays a minor role. Both scattered light and SERS images are well reproduced by simple model calculations. Due to the different signal generation and coherence properties, the combination of both imaging methods is a useful means in the characterization of optical properties of nanostructured metal surfaces.