Split-RingResonators.PDFVIP

CHIN. PHYS. LETT. Vol. 31, No. 6 (2014) 067801 Low Frequency Ultra-Thin Compact Metamaterial Absorber Comprising Split-Ring Resonators * LIN Bao-Qin(林宝勤)**, DA Xin-Yu(达新宇), ZHAO Shang-Hong(赵尚弘), MENG Wen(蒙文), LI Fan(李凡), ZHENG Qiu-Rong(郑秋容), WANG Bu-Hong(王布宏) Institute of Information and Navigation, Air Force Engineering University, Xi’an 710077 (Received 9 September 2013) We present a design of a low frequency ultra-thin compact and polarization-insensitive metamaterial absorber (MA). The designed MA is a two-layer structure, a periodic array of novel split-ring resonators (SRRs), which are constructed in an FR4 dielectric layer, and another ultra-thin grounded sheet is attached to the bottom. Numerical simulated results show that the proposed MA can realize effective absorption at the frequency 281.9 MHz, andits overall thickness is just only 0.29% of the resonant wavelength, the unit space is only 2.57%, and the absorbance is kept well for a wide range of incident angles for different polarizations. In addition, the proposed MA is changed into a more compact one when the inter-digital structures are introduced in the SRRs. One convenient experiment is carried out in a rectangular waveguide simulator. PACS: 78.20.Ci, 41.20.Jb DOI: 10.1088/0256-307X/31/6/067801 Electromagnetic metamaterials[1] are artificially and filters.[22] designed media, which exhibit unique electromag- In this Letter, we design a novel ultra-thin MA netic properties that are unattainable with natu- with much lower resonance frequency. Numerical sim- ral materials, such as the negative permittivity,[2] ulations demonstrate that the proposed MA can re- permeability,[3] refractive index,[4,5] and invisibility.[6] alize effective absorption at the frequency 281.9 MHz, Due to the peculiar electromag