Chern Ruey-Lin
Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan.
Opt Express. 2013 Jul 15;21(14):16514-27. doi: 10.1364/OE.21.016514.
The feature of spatial dispersion in periodic layered metamaterials is theoretically investigated. An effective medium model is proposed to derive the nonlocal effective permittivity tensor, which exhibits drastic variations in the wave vector domain. Strong spatial dispersion is found in the frequency range where surface plasmon polaritons are excited. In particular, the nonlocal effect gives rise to additional waves that are identified as the bonding or antibonding modes with symmetric or antisymmetric surface charge alignments. Spatial dispersion is also manifest on the parabolic-like dispersion, a non-standard type of dispersion in the medium. The associated negative refraction and backward wave occur even when the effective permittivity components are all positive, which is considered a property not available in the local medium.
从理论上研究了周期性分层超材料中的空间色散特性。提出了一种有效介质模型来推导非局部有效介电常数张量，该张量在波矢域中表现出剧烈变化。在表面等离激元极化激元被激发的频率范围内发现了强烈的空间色散。特别地，非局部效应产生了额外的波，这些波被识别为具有对称或反对称表面电荷排列的键合或反键合模式。空间色散也体现在类抛物线色散上，这是该介质中一种非标准类型的色散。即使有效介电常数分量均为正值，也会出现相关的负折射和反向波，这被认为是局部介质所不具备的特性。
