Terahertz Metamaterial Absorber Based on Graphene with Properties Optimised by Investigation of Plasma Parameters for Improved Device Performance

Abstract

Low-dimensional materials like graphene have tremendous potential for use in high-performance terahertz absorbers for a variety of practical applications. Direct growth techniques, such as plasma-enhanced chemical vapor deposition (PECVD), that offer control over the inherent features of those materials can further lead to affordable and scalable ways to construct effective absorber devices. Because it has a high degree of electromagnetic confinement in the terahertz range and tunability, graphene is an especially alluring plasmonic material. This study presents a terahertz absorber optimized by tailoring the electrical and physical characteristics of graphene sheets for use as a metamaterial. A correlation between device performance and plasma parameters in graphene growth has been found because parameters like thickness, carrier mobility, and carrier density of graphene sheets can be controlled during their growth during PECVD, which in turn can have a significant impact on the material's frequency-dependent complex conductivity. To build the ideal device, data from PECVD experiments have been thoroughly assimilated and utilized in device simulation to the maximum possible extent. The terahertz absorber uses a simplified and optimized rectangular ring resonator geometry and achieves single-band and narrow absorption of 100% upon using graphene with particular values of thickness, carrier density, and carrier mobility.