4th Physics Institute and Research Center SCoPE, University of Stuttgart, D-70569 Stuttgart, Germany.
ACS Nano. 2011 Oct 25;5(10):8202-11. doi: 10.1021/nn202876k. Epub 2011 Sep 7.
Plasmonic oligomer clusters are assemblies of closely packed metallic nanoparticles. They provide a rich set of spectral features such as Fano lineshapes and a simultaneous tunability of the supported resonances in the optical wavelength regime. In this study, we investigate numerically and experimentally clusters of plasmonic nanoparticles that exhibit multiple Fano resonances due to the interference of one broad superradiant mode and multiple narrow subradiant modes. In particular we investigate oligomers with multiple ring modes and elongated chains of nanoparticles surrounded by one ring of nanoparticles. We show that the number of nanoparticles and their respective arrangement in the cluster strongly influence the spectral position and modulation depth of the spectral signature of the supported modes. Our study opens up the pathway to "plasmonic super molecules" that show unprecedented tunability, which renders them highly suitable for applications such as multiwavelength surface-enhanced Raman scattering.
等离子体激元聚集体是紧密堆积的金属纳米粒子的集合。它们提供了丰富的光谱特征，如 Fano 线型和在光学波长范围内同时支持共振的可调谐性。在这项研究中，我们通过数值和实验研究了由于一个宽的超辐射模式和多个窄的亚辐射模式的干涉而表现出多个 Fano 共振的等离子体纳米粒子聚集体。特别地，我们研究了具有多个环模式和由一个纳米粒子环包围的拉长纳米粒子链的低聚物。我们表明，纳米粒子的数量及其在聚集体中的排列方式强烈影响支持模式的光谱特征的光谱位置和调制深度。我们的研究为“等离子体超分子”开辟了道路，它们表现出前所未有的可调谐性，非常适合多波长表面增强拉曼散射等应用。
