Herrmann L O, Valev V K, Aizpurua J, Baumberg J J
Opt Express. 2013 Dec 30;21(26):32377-85. doi: 10.1364/OE.21.032377.
The strong enhancement of electrical fields in subnanometer gaps of self-assembled gold nanoparticle clusters holds great promise for large scale fabrication of sensitive optical sensing substrates. Due to the large number of involved nanoparticles, however, their optical response is complex and not easily accessible through numerical simulations. Here, we use hyperspectral supercontinuum spectroscopy to demonstrate how confined optical modes of well defined energies are supported by different areas of the cluster. Due to the strong resonant coupling in those regions, the cluster essentially acts as a nanoscale optical sieve which sorts incident light according to its wavelength.
自组装金纳米粒子簇的亚纳米间隙中电场的强烈增强，为大规模制造灵敏的光学传感基板带来了巨大希望。然而，由于涉及大量的纳米粒子，它们的光学响应很复杂，难以通过数值模拟轻松获取。在这里，我们使用高光谱超连续谱光谱来证明簇的不同区域如何支持具有明确能量的受限光学模式。由于这些区域中的强共振耦合，该簇本质上充当了一个纳米级光学筛，根据入射光的波长对其进行分类。
