Broadband terahertz metamaterial absorber based on simple multi-ring structures

Abstract

Single-layer metallic rings are the effective structure cell which are widely used to design single-band and multiband perfect metamaterial absorbers owning to their electromagnetic resonance. However, the absorbers based on the single-layer metallic rings have a common shortcoming, that is the narrow absorption bandwidth. To overcome the limitations, here we proposed a single-layer, flexible and broadband terahertz metamaterial absorber, which consists of four sub-cells with multiple metal rings and a metal ground plane separated by a dielectric layer. By enhancing the coupling response between adjacent metallic rings and merging the adjacent resonant peaks of multi-resonators, we experimentally observed broadband characteristics at the terahertz band. The average absorption of 88% from 0.63 to 1.34 THz and the relative absorption bandwidth of 95% at the incident angle of 15o for TE polarization. Correspondingly, for TM polarization the absorption of more than 80% from 0.61 to 1.1 THz with the relative absorption bandwidth of 80% were also observed. The results went far beyond the previous single-layer absorbers based on metal rings and were much better than the fractal-cross structure reported recently [Kenney et al., ACS Photonics 4, 2604 (2017)]. We had reason to believe that the presented terahertz metamaterial absorber with broad absorption bandwidth and simple structure can find important applications in communication, stealth, energy harvesting systems and so on.

Simple Design of a Wideband and Wide-Angle Insensitive Metamaterial Absorber Using Lumped Resistors for X- and Ku-Bands

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Tunable Triple-Band Terahertz Absorber Based on Bulk-Dirac-Semimetal Metasurface

“…Terahertz (THz) technology has many potential prospects both in scientific research and practical applications, such as spectrum detection of material properties, non-destructive detection, biological sensing, medical diagnosis, security screening and high-speed wireless communication, etc. [1][2][3][4][5]. THz absorber (TA), an important field of terahertz technology, which is an indispensable component in the THz detectors, imagers, and sensors, has drawn great research interest.…”

Broadband Near-Infrared Absorber Based on All Metallic Metasurface

“…In 2008, Landy et al [1] first experimentally demonstrated the perfect metamaterial absorber, which works in microwave frequency band. Since then, many works concentrate on metamaterial absorber operating at frequency from microwave range [2,3] through terahertz [4,5], infrared [6,7], and into the visible region [8,9,10]. In the optical region, perfect metamaterial absorber has been an important branch of optical devices for its unique performance.…”