Localized Surface Plasmon Resonances in Spatially Dispersive Nano-Objects: Phenomenological Treatise
Localized Surface Plasmon Resonances in Spatially Dispersive Nano-Objects: Phenomenological Treatise
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DOI：
10.1021/nn400842m
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发表时间：
2013-05-01
期刊：
影响因子：
17.1
通讯作者：
Zayats, Anatoly V.
中科院分区：
文献类型：
--
作者：
Ginzburg, Pavel;Zayats, Anatoly V.
材料的非局部光学响应在纳米尺度上非常重要，它影响着许多光学现象，如电磁场约束和等离子体共振的光谱特性。在这里，我们提出了一种一般现象学方法来解释纳米级金属颗粒中的非局部材料极化率。非局部等离子体共振问题用空间域的积分-微分方程表示，采用弱形式求解，用有限元法实现，从而省去了附加边界条件的要求。以不同截面等离子体纳米棒和纳米管中的非局部涂抹效应为例进行了研究。非局域性的明显特征表现在势谱的干涉条纹和局域表面等离子体共振的显著频移。这些效应对于具有与参与光-物质相互作用的电子的德布罗意波长相当的几何特征的纳米粒子尤其重要。所提出的方法提供了一种通用的工具，用于任何类型的非定域的现象学解释，其唯一要求是系统响应的线性。
Nonlocal optical response of materials, important at the nanometric scale, influences numerous optical phenomena, such as electromagnetic field confinement and spectral characteristics of plasmonic resonances. Here, we present a general phenomenological approach to account for nonlocal material polarizabilities in nanoscale metal particles. The problem of nonlocal plasmonic resonances is formulated by an integro-differential equation in a space domain and solved by adopting its weak form, implemented in the finite element method, thus, dispensing with the requirements on additional boundary conditions. As an example, nonlocal smearing effects in plasmonic nanorods of various cross sections and nanotubes have been considered. Clear signature of nonlocality manifests itself in the interference fringes in the potential profile and a significant frequency shift of the localized surface plasmon resonances. These effects are especially important for nanoparticles with geometrical features comparable to the de Broglie wavelengths of electrons participating in the light-matter interactions. The proposed method provides a universal tool for phenomenological account of nonlocalities of any kind with the only requirement of linearity In system's response.