Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.
Nano Lett. 2010 Aug 11;10(8):3184-9. doi: 10.1021/nl102108u.
Clusters of plasmonic nanoparticles and nanostructures support Fano resonances. Here we show that this spectral feature, produced by the interference between bright and dark modes of the nanoparticle cluster, is strongly dependent upon both geometry and local dielectric environment. This permits a highly sensitive tunability of the Fano dip in both wavelength and amplitude by varying cluster dimensions, geometry, and relative size of the individual nanocluster components. Plasmonic nanoclusters show an unprecedented sensitivity to dielectric environment with a local surface plasmon resonance figure of merit of 5.7, the highest yet reported for localized surface plasmon resonance sensing in a finite nanostructure.
等离子体纳米粒子簇和纳米结构支持 Fano 共振。在这里，我们表明，这种由纳米粒子簇的亮模和暗模之间的干涉产生的光谱特征强烈依赖于几何形状和局部介电环境。这使得通过改变簇的尺寸、形状以及各个纳米簇组件的相对大小，可以在波长和振幅上对 Fano 谷进行高度灵敏的调谐。等离子体纳米簇对介电环境具有前所未有的敏感性，局部表面等离子体共振的优值为 5.7，这是在有限纳米结构中局部表面等离子体共振传感中报道的最高值。
