Research On Absorbing Metamaterials Based On The Local Effect Of Subwavelength Structure

With the development of research of the electromagnrtion. The electromagnetic wave can be found everywhere in our life. How to eliminate the dangers of it to us becoming a problem we must solve. Therefore, absorbing materials have been widely research,the research of absorbing materials are mainly concentrated in high absorption,low frequency, multi-band and wide frequency band. In this paper,we mainly focused on the absorber based on the subwavelength structured metamaterials in the microwave region.Main work and the conclusion are listed as follow:(1)We report the design, analysis, and simulation of quadruple-band metamaterial absorber(MMA) in the microwave region. The absorber is constructed of a delicate periodic patterned structures and a metallic background plane, separated by a dielectric substrate. By manipulating the periodic patterned structures, high absorption can be obtained at four specific resonance frequencies. Moreover, the significantly high absorptions of quadruple-peaks are persistent with polarization independence, and the influence of angle of incidence for both TE and TM modes was also elucidated. For explaining the absorption mechanism of proposed structures, the electric and magnetic field distributions and resistance matching principal were given. Importantly, the design idea has the ability to be extended to other frequencies, like terahertz, infrared and optical frequencies.(2)We report the design, analysis, and simulation of the low-frequency perfect metamaterial absorber(MMA) based on corrugated surface, which has very small unit-cell size. The proposed MMA consist of a regular square-array and a metallic background plane, separated by a corrugated surface with periodic square-pillar-array.Through the optimized design, the ratios between lattice constant and resonance wavelength for nearly-perfect and high absorption MMA are close to 1/15 and1/21,respectively. Moreover, the absorption peaks remain high with large angles of incidence for both transverse electric and transverse magnetic polarizations, which provide more efficient absorptions for oblique incident electromagnetic wave.(3)We report the design, analysis, and simulation of the wide frequency band metamaterial abosrber(MMA) in the microwave region. The absorber is cascading by some structures constructed of a basic absorbing structure. By manipulating the periodicpatterned structures, high-wide absorption can be obtained. To explain the absorption mechanism of suggested structures, the surface current and electromagnetic field distributions are given.