Simplify Parameter Metamaterials Electromagnetic Devices And Design

Based on the form-invariant of Maxwell's equations, design of metamaterial electromagnetic devices using coordinate transformation method to achieve arbitrary control of electromagnetic wave has been a research hotspot in recent years. Following this theory, lots of electromagnetic devices with novel functionalities have been proposed. However, the practical fabrication of these radial transformation devices is still difficult to achieve, for the material parameters are usually highly anisotropic, inhomogeneous and even singular. Therefore, it has very important significance to study the simplified parameters design of devices.By carrying out linear coordinate transformation along orthogonal directions, many kinds of metamaterials electromagnetic devices with nonsingular homogeneous material parameters are designed in this paper, including3D carpet cloak,3D wave concentrator,2D and3D electromagnetic transparent device. The relative permittivity and permeability expressions are derived, and the effectiveness of material parameter and the properties of electromagnetic device are validated by full-wave simulation using COMSOL software. The linear coordinate transformation avoids the singularity in the material parameters. Moreover, due to homogeneously stretching and compressing at orthogonal directions during the transformation, the resulted material parameters are homogeneous. This work expands the application of the coordinate transformation method, and will facilitate the practical implementation of metamaterial electromagnetic devices. The main contents of the paper contain the following four parts.In the first part, the design idea of2D radial transformation invisible cloak, wave concentrator and electromagnetic transparent device with arbitrary shape are described in detail, and the corresponding electromagnetic properties are simulated and analyzed.In the second part, the invisible properties for both2D and3D invisible cloaks with simplified parameters are analyzed in detail, and the3D carpet cloak with nonsingular homogeneous material parameters is designed.In the third part, material parameter distributions, focusing properties, and focusing reason of the2D wave concentrator with simplified parameters are deeply studied. Design strategy of3D wave concentrator with nonsingular homogeneous material parameters is first proposed, and the effect of different compressive ratios on the performance of the device is investigated. Besides, broadband properties and feasibility of wave concentrator in solar cell applications are discussed.In the fourth part, both2D and3D electromagnetic transparent devices composed of homogeneous and nonsingular material parameters are first proposed and designed. The material parameters equations of transparent device are derived. Moreover, the transparent properties, broadband properties and feasibility of electromagnetic transparent device in antenna protection are discussed.