Utilization of a Dual-Layer Graphene Structure for Slow Light Engineering in the Terahertz Band

The proposed structure comprises a unit cell with two dielectric substrates: SiO2 and nine graphene disks, positioned on the lower substrate. Additionally, a square patch of graphene is situated on the upper substrate. The conductive behavior of graphene at terahertz frequencies is described using a specialized model. The impedance and electrical characteristics of this structure are modeled through RLC relationships, and simulations have been conducted to analyze the interaction of terahertz waves with the structure. The results indicate that the Fermi energy of graphene can influence the resonance frequency of the structure, leading to variations in optical properties such as group delay and group velocity. Overall, the findings of this research highlight the potential for optical control and tuning in the terahertz band utilizing graphene and its metamaterials, presenting strategic capabilities for telecommunications and photonic applications.