Ultra-thin polarization independent broadband terahertz metamaterial absorber

Abstract

In this work, we present the design of a polarization independent broadband absorber in the terahertz (THz) frequency range using a metasurface resonator. The absorber comprises of three layers, of which, the top layer is made of a vanadium dioxide (VO 2 ) resonator with an electrical conductivity of σ = 200000 S/m; the bottom layer consists of a planar layer made of gold metal, and a dielectric layer is sandwiched between these two layers. The optimized absorber exhibits absorption greater than 90% from 2.54 -5.54 THz. Thus, the corresponding bandwidth of the designed absorber is 3 THz. Further, the thermal tunable absorption and reflection spectra have been analyzed by varying the electrical conductivity of VO 2 . The impact of the various geometrical parameters on the absorption characteristics has also been assessed. The physics of generation of broadband absorption of the proposed device has been explored using field analysis. Finally, the absorption characteristics of the unit cell has been studied for various incident and polarization angles.

Multi-Layered Metamaterial Absorber: Electromagnetic and Thermal Characterization

“…As the number of layers increased, the absorption peak and bandwidth of the non-atmospheric window band broadened. Gandhi et al presented the design of a polarization-independent broadband absorber in a THz frequency range using a metasurface resonator [30]. The absorber was composed of three layers, whose top layer was made with a vanadiumdioxide resonator of a conductivity σ = 200,000 S/m.…”

Optically transparent and flexible-assembled metasurface rasorber for infrared-microwave camouflage based on a hybrid anapole state

“…29–32 This specific function can be achieved by a rasorber, which allows electromagnetic waves in a desired band to pass efficiently but absorbs those outside the band. The design strategies of metasurface rasorbers in previous studies are usually based on fundamental electromagnetic dipole moments, 33 seldom employing higher-order electromagnetic multipoles and toroidal multipoles. In particular, metasurface rasorbers based on hybrid anapoles have not yet been reported.…”

Multi‐Band Polarization‐Independent Quasi‐Bound States in the Continuum Based on Tetramer‐Based Metasurfaces and Their Potential Application in Terahertz Microfluidic Biosensing

“…The vibration and rotation frequencies of most biomacromolecules are located in the terahertz band, and the corresponding resonance absorption peaks have fingerprint characteristics that can reflect the structure of matter. [ 1–6 ] This feature, along with the advantages of low energy, minor damage, and strong penetrability, greatly promotes the rapid development of terahertz biochemical sensing. [ 7–11 ] Besides, in 2019, the US Federal Communications Commission decided to open the 0.095 THz‐3 THz band as the 6G test frequency band, terahertz detection and filtering will play indispensable roles in commercial 6G and more advanced communication in the future.…”