Design of transparent cloaks with arbitrarily inner and outer boundaries

Abstract

In this paper, the efficient transformation optics method has been utilized to design and analyze two-dimensional (2D) transparent cloaks, structures that can physically protect the devices inside but do not affect their electrical performances at all. The general and explicit expressions for the material parameters of the transformed space are derived. 2D transparent cloaks with arbitrarily conformal and nonconformal inner and outer boundaries and those working in gradually changing background and layered media are designed. Full-wave simulations combined with the Huygens’ principle are applied to validate the transparency of the cloaks. The simulation results under different circumstances demonstrate that the proposed method is correct and efficient. The work introduced here makes important progress in the theoretical design of the transparent cloak and expands the application of the transformation optics method.

Homogeneous Multifunction Devices Designing and Layered Implementing Based on Rotary Medium

“…Besides invisible cloak, concentrator 13 – 18 , transparent device 19 – 22 , amplifying device 23 , shrinking device 24 – 26 and EM field rotator 27 – 29 have also attracted widespread attention for their special functions and properties. For example, concentrator endows the capability to enhance the EM field distribution in the core region and has potential application in the harnessing of light in solar cells or similar devices 14 , 15 , while transparent device has the capability to protect an antenna or other object inside the device without affecting their performance 20 , 22 . Amplifying device or shrinking device can make an arbitrary shaped object virtually acts as another one with different material parameters and geometrical size, and have potential applications in military camouflage and other communication engineering fields 23 , 24 .…”

Homogeneous transparent device and its layered realization

“…[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] Among various novel applications, transparent devices have recently attracted widespread attention due to their ability to protect the device inside without affecting their performance, and they have shown great potential in antenna protection. By using the compressing or stretching transformation method, a twodimensional (2D) transparent device was first proposed by Yu et al [30] Later, the arbitrarily shaped transparent devices with either conformal or non-conformal boundaries were proposed by Yang et al [31] and Mei et al, [32] and the general expressions of material parameters were developed. However, it is worth mentioning that the fabrication of such a device has seldom been reported due to the inhomogeneous and anisotropic properties of the material parameters.…”

Inverse design-based metamaterial transparent device and its multilayer realization

“…[25] Among various devices, metamaterial transparent devices have recently aroused great attention due to their capability of protecting the device inside without affecting their performance-an important property for radome structures. Circular and elliptical transparent devices were firstly proposed by Yu et al [26] Later, the general expressions of material parameters for a transparent device with arbitrarily conformal and non-conformal inner and outer boundaries are developed by Mei et al [27] The foregoing investigations are really attractive and hold great promise for application in antenna protection. However, coordinate transformation for these transparent devices is conducted along the radial direction, resulting in the necessary material parameters being highly anisotropic inhomogeneous.…”