Optical metrics relating to metallic absorption in representative plasmonic systems are surveyed, with a view to developing heuristics for optimizing performance over a range of applications. We use the real part of the permittivity as the independent variable; consider strengths of particle resonances, resolving power of planar lenses, and guiding lengths of planar waveguides; and compare near...

Broadband perfect absorber based on one ultrathin layer of the refractory metal chromium without structure patterning is proposed and demonstrated. The ideal permittivity of the metal layer for achieving broadband perfect absorption is derived based on the impedance transformation method. Since the permittivity of the refractory metal chromium matches this ideal permittivity well in the visible...

The dielectric nanosize dependence of BaTiO₃ powders was investigated by the slurry method, where two series of BaTiO₃ slurries with 10 vol% and 30 vol% solids loadings were prepared as model samples. Applying the Bruggeman-Hanai equation, the high-frequency limiting permittivity (ε(h)) of the slurries was extracted from the dielectric spectra. The ε(h) of the 10 vol% slurry showed abnormal siz...

We present preliminary results from a method for estimating the optimal effective permittivity for reconstructing microwave-radar images. Using knowledge of how microwave-radar images are formed, we identify characteristics that are typical of good images, and define a fitness function to measure the relative image quality. We build a polynomial interpolant of the fitness function in order to i...

The present paper reports the results of a numerical analysis of electric fields in random dielectric materials. The effective permittivity of a three-dimensional (3-D) dielectric mixture is calculated by the finite difference method. The results show the distribution of the effective permittivity of a mixture with different random inclusion positionings. New empirical mixing models are created...

A change in the relative proportions of a mixture of rubber tire dust and rice husks will cause a change in the mixture’s electrical permittivity and its ability to absorb electromagnetic energy. An openended coaxial probe was used in conjunction with three dielectric mixture equations (the Kraszewski equation, the Landau equation and the Lichtenecker equation) to obtain the dielectric properti...

The randomness in the structure of two-component dense composite materials influences the scalar effective dielectric constant, in the quasistatic limit. A numerical analysis of this property is developed in this paper. The computer-simulation models used are based on both the finite element method and the boundary integral equation method for twoand three-dimensional structures, respectively. ...

This study presents an analytical method for extracting the constitutive parameters of an isotropic two-dimensional magneto-dielectric thin cylinder (small radius compared with the wavelength). The method is based on the scattered far field information to a plane wave illumination. Three variations of the method are presented. First, the complex monostatic scattered fields of two orthogonal pol...

Bio-molecule when isolated from its natural ecological condition is subjected to rapid decay. This decay leads to change in polarization and permittivity of molecule. This study presents an experimental analysis of the decay pattern of pM concentration of insulin using whispering gallery mode (WGM) dielectric resonator (DR) method. Analysis is carried out by comparing the permittivity, relaxati...

The spectral representation of the effective complex permittivity of a two-component composite medium is used to develop an approach to coupling of various effective properties of a random mixture. The spectral function contains all information about the microstructure, hence providing a coupling link between the various effective properties of the same composite material. It is demonstrated th...