Departament de Física Aplicada i Òptica, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain.
ACS Nano. 2012 Sep 25;6(9):8415-23. doi: 10.1021/nn303243p. Epub 2012 Sep 4.
Control of the polarization distribution of light allows tailoring the electromagnetic response of plasmonic particles. By rigorously extending the generalized multiparticle Mie theory, we show that focused cylindrical vector beams (CVB) can be used to efficiently excite dark plasmon modes in nanoparticle clusters. In addition to the small radiative damping and large field enhancement associated to dark modes, excitation with CVB can give place to unusual phenomenology like the formation of electromagnetic cold spots and the generation of Fano resonances in highly symmetric clusters. Overall, the results show the potential of CVB to tailor the plasmonic response of nanoparticle clusters in a unique way.
光的偏振分布控制可使等离子体粒子的电磁响应得以调整。通过严格扩展广义多粒子 Mie 理论，我们表明聚焦的圆柱矢量光束（CVB）可用于有效地激发纳米粒子簇中的暗等离子体模式。除了与暗模式相关的小辐射阻尼和大场增强外，用 CVB 激发还可能产生异常现象，例如在高度对称的簇中形成电磁冷点和产生 Fano 共振。总体而言，这些结果表明了 CVB 以独特的方式调整纳米粒子簇的等离子体响应的潜力。
