Ultrathin multiband gigahertz metamaterial absorbers

Abstract

We propose ultrathin multiband metamaterial absorbers in the microwave frequencies in which the design, analysis, fabrication, and measurement of the absorbers working in multiple bands are presented. The metamaterial absorbers consist of a periodic arrangement of different scales of electric-field-coupled-LC (ELC) resonators and a metallic background plane, separated by only 1 mm dielectric spacer. By tuning the scale factor of the ELC unit cells, we achieve independently multiple absorptions at different customized frequencies. Experiments demonstrate excellent absorption rates in the designed frequency bands over wide angles of incident waves for both transverse electric and magnetic polarizations. The explanation to the physical mechanism of the multiband metamaterial absorber is presented and verified.

Al/SiOx/Al single and multiband metamaterial absorbers for terahertz sensor applications

“…These metamaterial films typically consist of a periodic-patterned metal layer, a dielectric spacer, and a ground plane. [12][13][14][16][17][18][19][20][21][22][23][24][25] Multiband absorbers have also been demonstrated in GHz, [17][18][19] 0.1 to 1 THz, 20,21 1 to 10 THz, [22][23][24] and IR 25,26 ranges. However, the multiband absorbers in the 1 to 10 THz range rely on 8-μm 22 and 4-μm 23,24 thick layers of polyimide as the dielectric spacer layer.…”

Wide-Angle Polarization Independent Triple Band Absorber Based on Metamaterial Structure for Microwave Frequency Applications

“…After being inspired by Pendry et al's work [4,5], Shelby et al [6] experimentally illustrated the first lefthanded MTM in 2001 at microwave frequency regime. In last few years, MTM has been used in various electromagnetic applications, such as antenna [7], cloaking [8], filter [9] and absorber [10,11]. Nowadays, MTM based absorbers have been discussed due to their advantages of ultra-thin thickness, near unity absorption and many more, over conventional absorbers.…”

Ultra-Compact Metamaterial Absorber With Low-Permittivity Dielectric Substrate

“…These metamaterial absorbers can operate at almost arbitrary frequency spectra ranged from radio frequencies, microwave and terahertz frequencies, to even optical frequencies [8][9][10][11][12][13]. Moreover, strategies for expanding the operating bandwidths of MAs, such as dual-band [14,15], triple-band [16,17], multiband [18,19], band-tunable [20,21], broad-band [22,23], and ultra-broad-band [24,25] designs, have also been reported in recent years. Simultaneously, the theoretical analysis methods including classic electromagnetic theory [7], interference theory [26], and equivalent circuit/transmission line theory [27] are developed to analyze and guide the design procedures and explain the appeared exciting absorbing properties.…”