Dual-Band Terahertz Metamaterial Absorber With Polarization Insensitivity and Wide Incident Angle

Abstract

Abstract-This paper presents the design, simulation and measurement of a dual-band terahertz metamaterial absorber with polarization-insensitivity and wide incident angle. The unit cell of the metamaterial consists of top resonator structures and low metallic ground plane, separated by an isolation material spacer to realize both electric and magnetic resonances. The physical mechanism of dual-band absorption and the sensitivity to the polarization direction and incident direction of the EM wave are theoretically investigated by simulating the x-component and normal component electric field distribution, current distribution on ERRs and metallic ground plane, and distribution of power flow and loss at the resonance frequencies as well as different modes EM waves, based the FDTD calculated method, respectively. The results show that the absorber is not only correctly coupling to the incident electric field and magnetic field, but also can trap the input power into specific positions of the devices and absorb it, besides insensitivity to the polarized angle and incident angle. Moreover, the experiment demonstrates that the absorber achieves two strong absorptions of 82.8% and 86.8% near 1.724 and 3.557 THz.

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

“…[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. Since microbolometer pixel membranes are typically about 0.5-μm thick, 11 the use of 4-to 8-μm films would substantially increase thermal capacitance, negatively impacting real-time imaging performance due to an increase in the thermal time constant.…”

DESIGN AND 3-D PARTICLE-IN-CELL SIMULATION OF A 140 GHz SPATIAL-HARMONIC MAGNETRON

“…Although various components have been developed for THz applications [5][6][7][8][9][10][11][12][13][14][15][16][17][18], high power, low cost, and compact THz sources are not readily available [19]. With the rapid advancement of multi-physics based codes, which provide the possibility of simulating the nonlinear beam-wave interaction dynamics [20][21][22][23][24], extending the operating frequency of the existing microwave tube designs [25][26][27][28][29] has become a promising approach for developing compact and powerful THz sources [30][31][32][33][34][35][36].…”

A Metamaterial Based Microwave Absorber Composed of Coplanar Electric-Field-Coupled Resonator and Wire Array

“…Compared to the traditional microwave absorber, the thickness of resonant MMA can be much thinner, and the fabrications of MMA are low cost and simple. It should be noted that most of the MMAs, to avoid power transmission on the other side of the absorber, are equipped with a metallic backing plate [10][11][12][13][14]; however, the presence of backing plates may be disadvantageous in stealth applications [15]. The configuration of the previously reported metallic backplane-less MMAs involves the realization of both the metallic pattern with the negative real part of the permittivity and permeability.…”