Comparison of Characteristic about Absorbing Electromagnetic Wave between Double-Negative Metamaterials and General Dispersive Media

Soviet scientist Veselago [1] indicated in 1968 that media with negative permittivity and permeability would have distinct electromagnetic characteristic. In 2001, Inspired by the work of Pendry et al., Smith et al. constructed a composite "medium" in the microwave regime by arranging periodic arrays of small metallic wires and split-ring resonators. This media can also be mentioned double-negative (DNG) metamaterials, Since then, various ideas and suggestions for potential applications of metamaterials have been mentioned. In this paper, First, Lossy Drude polarization and magnetization models [2] are used to simulate the DNG media. The time domain equations solved with the finite-difference time-domain method (FDTD) simulator for the matched DNG media are presented. The discretized E
_z
and J
_z
of TM case in the 2D-FDTD simulators are given. Second, by comparing with the result in reference [2], the paper's method and program are validated. The broadband backward scattering of metallic column covered by different media layer is given in fig. 1. Because of DNG media's impedance matched to free space, its character of absorbing electromagnetic wave is better than general dispersive media. From fig.2, one finds that when DNG media's depth d, plasma frequency omega
_p
and damping frequency increase, the Radar Cross Section decrease in quite broad frequency bands. The bigger DNG media's plasma frequency and damping frequency, the higher the best absorbing frequency band is.