Analysis of magnetic response of circular arrangement of RF replicas of isotropic plasmonic spheres

Several designs of structures that behave similarly to plasmonic spheres but in the RF regime (“RF replicas”) have been introduced recently. These replicas enabled “scaled RF experiments” of future optical 1D and 2D plasmonic structures. However, an investigation of the 3D structures was not possible due to inherent anisotropic nature of RF replica. Here, this drawback is overcome by a novel design of isotropic RF replica based on a system of three orthogonal inductively loaded dipoles with capacitive hats. Full-wave simulations revealed an inversion of the electric field vector inside the sphere, which is a characteristic of plasmonic behavior. This inversion is almost completely independent on the polarization of the incoming plane wave proving isotropy. The idea of magnetic plasmon is also investigated by numerical analysis of the waveguide demonstrator loaded with new RF replicas. All numerical results are in a good agreement with the theoretical predictions proving that is indeed possible to excite the magnetic moment in a 3D arrangement of plasmonic spheres.