Tunable six-band miniaturised metamaterial absorber for IoT and THz imaging applications

this article, a multi-band polarization-insensitive metamaterial absorber is designed for THz imaging and EMI shielding. A unique oval-shaped structure with three circular ring-shaped resonators is proposed with a unit cell dimension of36×36×19.6μm3. The absorbance of the proposed multiband MMA is 98.57%, 90%and 99.85% at 5.58, 7.98-8.84, 11.45THz frequency respectively. Return loss is nearly the same for the changing incident and polarization angle. Therefore, this metamaterial absorber with a wide range of polarization insensitivity is found and it is also suitable for quantum RADAR Imaging, energy harvesting, and optoelectronic devices.

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Ultrathin polarization-insensitive tri-band THz perfect metamaterial absorber

EPJ Applied Metamaterials ◽

10.1051/epjam/2020003 ◽

2020 ◽

Vol 7 ◽

pp. 2

Author(s):

Zhaomei Liu ◽

Xingxing Han ◽

Aixia Wang

Keyword(s):

Cell Structure ◽

Metamaterial Absorber ◽

Q Factor ◽

Simulated Spectrum ◽

Thz Imaging ◽

Potential Applications ◽

Polarization Insensitive ◽

Perfect Metamaterial Absorber ◽

Sandwiched Structure ◽

Patch Resonators

In this paper, an ultrathin and polarization-insensitive THz perfect metamaterial absorber (PMA) was proposed using the traditional sandwiched structure with circular patch resonators on the top layer. The simulated spectrum shows that the proposed PMA has three distinctive absorption peaks at f1 = 0.8 THz, f2 = 2.28 THz and f3 = 3.62 THz, with absorbance of 96.7%, 97.9% and 99.8%, respectively. The electric field distributions of the PMA reveal that the absorption mainly originates from the standing wave resonances between the top and bottom layers. The proposed PMA is polarization insensitive due to its axisymmetric unit cell structure. By adjusting the structure parameters, the resonance frequency, intensity and Q-factor of absorption peak can be tuned effectively. Our design may find potential applications in THz imaging, sensing and signal detection.

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Liquid Crystal Tunable Dielectric Metamaterial Absorber in the Terahertz Range

Applied Sciences ◽

10.3390/app8112211 ◽

2018 ◽

Vol 8 (11) ◽

pp. 2211 ◽

Cited By ~ 2

Author(s):

Shenghang Zhou ◽

Zhixiong Shen ◽

Ruiyun Kang ◽

Shijun Ge ◽

Wei Hu

Keyword(s):

Numerical Simulation ◽

Liquid Crystal ◽

Modulation Depth ◽

Metamaterial Absorber ◽

Terahertz Range ◽

Absorption Peak ◽

Thz Imaging ◽

Applied Bias ◽

Pillar Array ◽

Thz Range

In this paper, we propose a tunable dielectric metamaterial absorber in the terahertz (THz) range. The absorber is composed of a silicon pillar array embedded in a liquid crystal (LC) layer, which is sandwiched by two graphene electrodes. By way of varying the applied bias, the LC orientation can be continuously tuned. At a saturated bias, all LCs are vertically driven, and an absorption peak of 0.86 is achieved at 0.79 THz. When the bias is turned off, the same LCs are horizontally aligned, and the absorption peak degenerates into two smaller ones. A 47% modulation depth at 0.79 THz is obtained via numerical simulation with experimental feasibility considered. Such an active THz dielectric absorber may be utilized as part of various active THz apparatuses in THz imaging, sensing, switching, and filtering.

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Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonators

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200145 ◽

2020 ◽

Vol 91 (3) ◽

pp. 30901

Author(s):

Yibo Tang ◽

Longhui He ◽

Jianming Xu ◽

Hailang He ◽

Yuhan Li ◽

...

Keyword(s):

Transverse Electric ◽

Surface Current ◽

Dielectric Substrate ◽

Transverse Magnetic ◽

Metamaterial Absorber ◽

Absorption Peak ◽

Dual Band ◽

Single Peak ◽

Wide Angle ◽

Surface Current Density

A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.

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