Ultrathin terahertz twisted split-ring broadband absorber for high-speed communication

Abstract In this study, an ultra-broad terahertz absorber based on a non-symmetric twisted split-ring resonator with the introduction of vanadium dioxide (VO 2 ) inside the splits is demonstrated. Owing to its excellent thermal, mechanical and optical properties, an ultrathin layer of silicon dioxide (SiO 2 ) is used as a dielectric spacer. The simulated result illustrates an absorption above 90% over the range of frequencies 0.95–2.4 THz. Furthermore, VO 2 used in the gap enables dynamic control over the interaction with terahertz waves. At the same time, tuning has been achieved placing single layer of graphene below reverted split ring resonators isolating it from SiO 2 dielectric spacer. Thus, the proposed absorber finds application in next generation sensing, intelligent switching and tunable terahertz filtering, photovoltaic device, spectroscopy, high speed wireless networks.