Dynamically tunable terahertz metamaterial absorbers integrating with active materials have been widely explored. However, there are still problems that need to be urgently solved, such as modulation depth deficiency, a lack of multiparameter-tunable characteristics, and so on. In this paper, absorber composed two concentric double-opening resonant rings is proposed. Semiconductor silicon germa...

A broadband adjustable absorber operating in the terahertz (THz) range is presented based on a vanadium dioxide (VO2) multiple ring structure with certain gap design. The dynamic absorption regulation of realized by utilizing phase-change characteristics VO2, which easily affected external temperature. simulation results show that when temperature reaches 350 K, conductivity VO2 can reach 2 × 1...

This paper presents an simulation study using CST microwave studio. In this work very simple design are used based on metamaterial to construct perfect absorber. It is a semi-square copper loop placed top of dielectric layer separate from ground plate. structure provides two absorption region with peaks in average 99.98%. due dipole resonance the main and secondary diameter ring. addition, dime...

The development of transparent radio-frequency electronics has been limited, until recently, by the lack of suitable materials. Naturally thin and transparent graphene may lead to disruptive innovations in such applications. Here, we realize optically transparent broadband absorbers operating in the millimetre wave regime achieved by stacking graphene bearing quartz substrates on a ground plate...

We investigate a novel implementation of hyperbolic metamaterial (HM) at far-infrared frequencies composed of stacked graphene sheets separated by thin dielectric layers. Using the surface conductivity model of graphene, we derive the homogenization formula for the multilayer structure by treating graphene sheets as lumped layers with complex admittances. Homogenization results and limits are i...

This paper presents an comprehensive study of light trapping and absorption enhancement in graphene through metallic plasmonic structures and shows a strategy to realize both ultrabroadband and strong absorption enhancement. Three different plasmonic absorber designs are investigated by numerical simulations. The excitation of localized plasmons in the metallic structures significantly enhances...