Broadband, polarization insensitive and tunable THz metamaterial absorber using graphene and phase change material

Abstract

Metamaterials are artificially-engineered materials with features that are not easily evident in naturally occurring materials. They can be used for perfect lenses, invisibility cloaking, perfect absorption and transmission and other applications because they exhibit novel properties such as left-handed behaviour, a negative refractive index, a classical analog of electromagnetically-induced transparency, extraordinary transmission, negative Doppler effect and more. Metamaterial-based perfect absorbers are potential candidates for practical use as perfect absorbers. In this study, we looked at a novel strategy to build a graphene metamaterial (GMM) based terahertz (THz) absorber with dual-mode functionality, tunability and broadband absorption. We carried thorough simulations on four alternative configurations and observed the maximum absorption and its efficiency. The absorber is designed to work in two unique modes, increasing its suitability for various THz applications, by manipulating resonant structures and the materials. We also did detailed simulation on five distinct configurations of tuned resonant structures, which differed from those in the previous structures, and concluded that the optimized structure with phase change material (PCM) can accomplish bandwidth almost twice as large. Phase change materials are promising possibilities for electronic Flash memory. They are often utilized in commercial optical disks and rewritable media. Phase change material (PCM) is extraordinary compounds with unique switchable properties leading to an explosion of new applications in the field of electronics and photonics. Furthermore, the absorber is polarization insensitive, has a wide viewing angle and responds quickly. Metamaterial structures are mainly three layered. Two optimized structures of metamaterial absorbers have been proposed. This study gives insight into the new method that increases the high absorption width, as well as the great potential in the multifunctional modulator, considering with and without the phase transition material. Our primary goal is to design a graphene-based metamaterial absorber that can achieve near unity frequency absorption that has maximum bandwidth. We have designed simple structure compared to the existing hybrid absorbers that can give nearly frequency bandwidth 7.69THz dualband and multiband absorption. Furthermore, we demonstrated step-by-step reliable methodologies to the fabrication of graphene-based metamaterial.