Fingers Crossed: Optical Activity of a Chiral Dimer of Plasmonic Nanorods
Fingers Crossed: Optical Activity of a Chiral Dimer of Plasmonic Nanorods
复制标题
DOI：
10.1021/jz200279x
复制
发表时间：
2011-04-21
影响因子：
5.7
通讯作者：
Liz-Marzan, Luis M.
中科院分区：
文献类型：
--
作者：
Auguie, Baptiste;Lorenzo Alonso-Gomez, Jose;Liz-Marzan, Luis M.
我们从理论上研究了等离子体纳米天线的二聚体的光学活性，模拟了具有两个孤立生色团的分子的几何形状，这种情况在有机化学中通常被描述为激子耦合。随着系统规模的增加和接近可见光的波长，产生了等离子体情况下所特有的各种丰富的效应。粒子对光的散射在非常小的星团中可以忽略不计，强烈地扰动并最终主导着光学活性。此外，具有与入射光波长相称的粒子间间隔的二聚体中的延迟效应影响粒子之间的电磁耦合，并导致不对称的圆二色谱。我们确定了有效相互作用的条件，并预测了非常大的各向异性因子。
We investigate theoretically the optical activity of a dimer of plasmonic nanoantennas, mimicking the geometry of a molecule with two isolated chromophores, a situation commonly described as exciton coupling in organic chemistry. As the scale of the system increases and approaches the wavelength of visible light, a rich variety of effects arise that are unique to the plasmonic case. Scattering of light by the particles, negligible in very small clusters, strongly perturbs, and eventually dominates, the optical activity. Additionally, retardation effects in dimers with an interparticle separation commensurate with the wavelength of the incident light affect the electromagnetic coupling between the particles and lead to an asymmetric circular dichroism spectrum. We identify conditions for efficient interaction and predict remarkably large anisotropy factors.