Study On Electromagnetic Wave Propagation In Double Negative Metamaterials And Layers Of Soil Media

Soviet scientist Veselago indicated in 1968 that media with negative permittivity and permeability would have distinct electromagnetic characteristics. Since American Smith et al fabricated double negative metamaterial (DNG) whoseεandμare negative by using Pendry's theoretical results for the first time in 2001, the study of DNG has become a conspicuous front field in international science field.First, we introduce the basic mechanism of DNG. The experimental progresses in research on DNG are surveyed. Several kinds of electromagnetic characters are studied. The applied future of DNG is prospected.Second, with DNG's constructive relation, we deduce the differential equations which describe characters of electromagnetic wave in DNG by combining the relation between D and E with the relation between ? t and jω. We obtain DNG's FDTD formulation by dispersing them. The FDTD method is capable of correctly computing electromagnetic propagation and scattering in DNG. Wave propagation in DNG is simulated by one-dimension FDTD. We discussed DNG's causality and negative index of refraction effect. The foci effect et al physics characteristics as electromagnetic wave propagating in DNG plate are simulated by two-dimension FDTD. We compute the scattering characteristics of a metallic column in two-dimension and a metallic object in three-dimension covered with DNG. The DNG's shield application is discussed.Finally, we investigate the polarization and decay characters of plane wave irradiating the soil media. By using one-dimension FDTD method we simulates the decay of double exponential pulse through the soil media, and its refractive time-domain wave shape is discussed in detail. Scattering Transfer Function (STF) method is introduced, and the combining of propagation matrices method and STF method simulates the decay of differential Gaussian pulse through layers of soil media. The law of polarized angles varied with frequency and the shape of double exponential pulse are presented. We conclude that the direction of plane wave propagation is denoted by the direction of the averaged power flow density.