Surface ferromagnetism as a basis for the creation of planar metamaterials

In this work, we study the influence of the surface on the energy of spin excitations of a ferromagnetic crystal in the Heisenberg model, with a particular focus on the possibility of using this effect to create planar metamaterials.

Controllable Fano-like Resonance in Terahertz Planar Meta-Rotamers

Meta-molecules composed of meta-atoms exhibit various electromagnetic phenomena owing to the interaction among the resonance modes of the meta-atoms. In this study, we numerically investigated Fano-like-resonant planar metamaterials composed of meta-molecules at terahertz (THz) frequencies. We present meta-rotamers based only on the difference in the spatial position of their component meta-atoms (C- and Y-shapes) that can be interconverted by rotations and have tunable Fano-like resonance. This is because of the cooperative effects determined by the spatial coupling conditions of the nodes and antinodes of electric-dipole and inductive–capacitive (LC) resonances of the meta-atoms. The findings of this study provide potential options for exploring novel THz devices and for engineering high-level functionalities in metamaterial-based devices.

A Metasurfaces Review: Definitions and Applications

This paper is a critical review of metasurfaces, which are planar metamaterials. Metamaterials offer bespoke electromagnetic applications and novel properties which are not found in naturally occurring materials. However, owing to their 3D-nature and resonant characteristics, they suffer from manufacturing complexity, losses and are highly dispersive. The 2-dimensional nature of metasurfaces allows ease of fabrication and integration into devices. The phase discontinuity across the metasurface offers anomalous refraction, thereby conserving the good metamaterial properties while still offering the low-loss characteristics. The paper discusses salient features and applications of metasurfaces; wavefront shaping; phase jumps; non-linear metasurfaces; and their use as frequency selective surfaces (FSS).