Electromagnetic Waves

Effects of Interaction of Electromagnetic Waves in Complex Particles Part 2

Near-field effects In the case of compact aggregates/media the electromagnetic interaction becomes even more complex, because the electromagnetic field in the close vicinity of the scattering particle is inhomogeneous due to the lag of the wave within the particle with respect to the incident wave. This effect is mostly expressed if the scatterer is comparable […]

Effects of Interaction of Electromagnetic Waves in Complex Particles Part 3

Spectral manifestation of coherent backscattering In Section 3.2 we discussed how coherent backscattering affects intensity and polarization phase curves producing there brightness and polarization opposition effects. Recently it has been found that coherent backscattering also manifests itself in spectral data. It affects the depth of the absorption bands and makes it dependent on the phase […]

Models for Scattering from Rough Surfaces (Electromagnetic Waves) Part 1

Introduction Models for scattering of electromagnetic waves from random rough surfaces have been developed during the last two centuries and the scientific interest in the problem remains strong also today due to the importance of this phenomenon in diverse areas of science, such as measurements in optics, geophysics, communications and remote sensing of the Earth. […]

Models for Scattering from Rough Surfaces (Electromagnetic Waves) Part 2

The Kirchhoff approximation In this section we shall consider the Kirchhoff (also sometimes referred to as the tangent plane approximation) approach to describe the scattering from rough surfaces, which was one of the first methods applied. We will consider surfaces with random surface profiles (i.e. not period surfaces) and within the context of the vector […]

Models for Scattering from Rough Surfaces (Electromagnetic Waves) Part 3

The small perturbation method The Small Perturbation Method (SPM) belongs to a large family of perturbation expansion solutions to the wave equation. The approach is based on formulating the scattering as a partial differential equation boundary value problem. The basic idea is to find a solution in terms of plane waves that matches the surface […]

Electromagnetic Wave Propagation in Circular Tunnels (Electromagnetic Waves)

Introduction The problem of guided wave propagation in a wave guide with imperfectly reflecting boundaries arises in several applications, such as propagation in mine tunnels and in screened surface wave guides. In recent years, many studies have been carried out on the propagation characteristic of radio waves in tunnels in UHF band [1-2]. From the […]

Propagation of Electromagnetic Waves in Thin Dielectric and Metallic Films Part 1

Introduction Matrix formalism is a very systematic method to find the reflectance or transmittance in a stratified medium consisting of a pile of thin homogeneous films. Fitting experimental values of reflectance curve to expressions obtained from the matrix formalism method is an efficient method to estimate the refractive index (n) of a dielectric and/or the […]

Propagation of Electromagnetic Waves in Thin Dielectric and Metallic Films Part 2

Wave propagation in dielectric films Let us consider a dielectric film of thickness d6 overlaying the metal film in Figure 2. We will be assuming that the top surface of the overlaying dielectric is bounded by the semi-infinite air medium. The characteristic matrix M for the sub-system of four layers can be expressed as: where […]

Propagation of Electromagnetic Waves in Thin Dielectric and Metallic Films Part 3

Photonic bandgap in metallic periodic gratings Resonant surface plasmon (SP) coupling involving metallic periodic gratings has been extensively studied over the past years and more recently in work looking at photonic devices (Park et al., 2003; Barnes et al. 2003; Ebbesen et al., 1998; Ye & Zhang, 2004) surface-enhanced Raman scattering (Sheng et al., 1982) […]

Quasi-optical Systems Based on Periodic Structures (Electromagnetic Waves) Part 1

Introduction Open resonators and open waveguides are widely used in millimeter and submillimeter wave electronics because they provide lower loss and higher Q-factor in comparison to the standard closed structures [Valitov et al., 1969; Shestopalov, 1985; Weinstein, 1966, 1995] . Examples of high performance measurement equipment employing open resonators (based on spherical or semispherical mirrors) […]

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