An Active Broadband Perfect Absorber Metamaterial Based on Hexagonal-Patterned Vanadium Dioxide.

In this work, we designed and theoretically investigated an adjustable perfect absorber metamaterial according to vanadium dioxide (VO 2 ). The VO 2 is a phase change material. By controlling its electrical conductivity from 2 × 10 2 to 2 × 10 5 S/m, the absorption continuously changed from 3.92 % to 100 % . The wider bandwidth and flexibility in selecting perfect absorption in the frequency range of 6.5 until 7.90 Thz are enhanced compared with other published VO 2 -based terahertz absorbers. We applied four common physical approaches to show the validation of results. These results are confirmed using the interference cancellation, modulation depth, electric field, surface current analysis, and impedance matching theory. Also, we investigate the influence output absorption spectrum by changing structure parameters. Therefore, the present THz perfect absorber has a vast capacity for profitable usages, such as photochemical energy absorption, modulating, sensing, cloaking, and stealth devices. [ABSTRACT FROM AUTHOR]