Theory of mesoscopic magnetism in meta-materials

介电光子晶体Meta材料的介观磁性：拓扑结构和非均匀展宽

Mesoscopic magnetism in dielectric photonic crystal meta materials: topology and inhomogeneous broadening

我们考虑由二维介质棒型光子晶体制成的Meta材料。最近发展的均匀化理论内的磁响应进行了研究，我们特别研究的拓扑结构和非均匀加宽的影响。虽然拓扑结构本身主要影响Mie谐振频率，但我们发现，当dR/R 0>> ε“/ε”时，介质棒的拓扑半径R的色散可能导致显著的非均匀加宽和负μ现象的抑制，其中ε = ε“+i* ε”是介质棒的相对介电函数。

Revealing topological phase in Pancharatnam-Berry metasurfaces using mesoscopic electrodynamics

Relying on the local orientation of nanostructures, Pancharatnam-Berry metasurfaces are currently enabling a new generation of polarization-sensitive optical devices. A systematical mesoscopic description of topological metasurfaces is developed, providing a deeper understanding of the physical mechanisms leading to the polarization-dependent breaking of translational symmetry in contrast with propagation phase effects. These theoretical results, along with interferometric experiments, contribute to the development of a solid theoretical framework for arbitrary polarization-dependent metasurfa…

Broadband optical magnetism in chiral metallic nanohole arrays by shadowing vapor deposition

We show that broadband optical magnetism can be achieved through incorporating multi-scaled 3D metallic meta-elements into Z-shaped nanohole arrays. The broadband effect arises from the excitation of multiple magnetic resonances in the meta-elements at different wavelengths. Moreover, the nanohole arrays exhibit a large transmission difference for left- and right-handed circularly polarized incident light due to the chiral arrangement of the meta-elements. More importantly, we have realized experimentally the broadband behavior for the optical range in Ag nanohole arrays fabricated by using a …

Practical Limits of Achieving Artificial Magnetism and Effective Optical Medium by Using Self-Assembly of Metallic Colloidal Clusters

The self-assembly of metallic colloidal clusters (so called plasmonic metamolecules) has been viewed as a versatile, but highly effective approach for the materialization of the metamaterials exhibiting artificial magnetism at optical frequencies (including visible and near infrared (NIR) regimes). Indeed, several proofs of concepts of plasmonic metamolecules have been successfully demonstrated in both theoretical and experimental ways. Nevertheless, this self-assembly strategy has barely been used and still remains an underutilized method. For example, the self-assembly and optical utilizatio…

Optical Magnetism in Planar Metamaterial Heterostructures

Harnessing artificial optical magnetism requires rather complex two- and three-dimensional structures, examples include split-ring and fishnet metamaterials and nanoparticles with non-trivial magnetic properties. By contrast, dielectric properties can be tailored even in planar and pattern-free, one-dimensional (1D) arrangements, for example metal/dielectric multilayer metamaterials. These systems are extensively investigated due to their hyperbolic and plasmonic response, which, however, is considered to be limited to TM polarization, based on the general consensus that they do not possess in…

光学鱼网形超材料有效材料参数的有效性

Validity of effective material parameters for optical fishnet metamaterials

虽然显示人工磁性的光学超材料是介观系统，但它们经常被描述为有效材料参数。但由于固有的非局域（或空间色散）效应，可以预料，这种方法通常只是一个粗略的近似，是没有物理意义的。为了研究关于分配的有效材料参数的限制，我们提出了一种技术来检索的有效介电常数和磁导率张量的频率相关元素的任意角度的入射和应用的方法示例性的渔网超材料。事实证明，对于渔网超材料，只有在对波长/晶胞尺寸比施加相当严格的约束时，才能引入真正的有效材料参数。不幸的是，它们仅在远离引起这种渔网超材料的许多设想应用所需的磁响应的共振的地方才能满足。我们的工作清楚地表明，当代光学超材料的介观性质和相关的空间色散，显示人工磁性禁止传统的有效材料参数的有意义的介绍。