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The dual mode operation of a nanodipole is demonstrated using a plasmonic core-shell particle load. Specifically, the fact that the latter exhibits an equivalent Lorentz type permittivity is utilized, in order to achieve either a capacitive or an inductive impedance response. Consequently, when such a particle is inserted within the gap defined by the nanodipole arms, the current conduction across...
A transmission reflection based waveguide technique has been proposed to calculate the permittivity and permeability of thin film samples. Known thin film materials have been studied to validate the technique. The measurements have been carried out in the frequency range from 5.85 GHz to 12.4 GHz. The possible sources of errors in the measurement of scattering parameters have been identified and methods...
The absorption of microwave energy by different materials e.g. rocks, soils and minerals is highly dependent on their dielectric properties. For the design of microwave cavities to process materials using microwaves a detailed knowledge of the response of the material to microwave radiation is required. This response is mainly influenced by the complex permittivity of the material under test. The...
A simple two-standard calibration procedure for determining the permittivity of a material from the propagation constant measured with planar transmission lines is presented. The suitability of this procedure is demonstrated by using a coplanar waveguide transmission-line sensor to measure the permittivity of five liquids, covering a wide range of complex permittivity. The results agree closely with...
A new method for calculating the broadband permittivity of non-magnetic, low-loss materials, from measured s-parameters made on a material sample placed in a transmission line, is proposed. The method assumes that the real part of permittivity can be modeled as a linear function of frequency with a negative slope. The imaginary part of permittivity is then calculated as the Hilbert transform of the...
Low Temperature Co-Fired Ceramic (LTCC) technology is one of the most widely used technologies for producing reliable electronic components, modules, and sensors, capable for working in high temperature applications and applications requiring low dielectric losses. In this paper characterization of two dielectric LTCC tapes (Heraeus AHT 01-005 and Heraeus AHT 08-047) is presented. The virtual relative...
Permittivity of granular type material (GTM) is determined by waveguide reflection/transmission method which is considered most accurate in dielectric material characterization. In this process, GTM is mixed with another host medium. In the simulation, GTM and host medium both are assumed to have known value of complex permittivity and GTM permittivity is extracted from the observed linear relationship...
This work focuses on multilayer composite material modeling. A surface model of two reinforced woven fiberglass composites (polyamide- and epoxy-based) is built using a multilayer effective media theory and a layered anisotropic material model embedded in a Method of Moment solver. Experimental characterizations of the electromagnetic complex relative permittivity of these materials are done using...
In this study, an analytical procedure to synthesize a biphasic composite panel with spherical inclusions is developed. The procedure is based on the knowledge of a frequency dependent Debye parameters associated to a homogeneous material with desired shielding performance. The proposed procedure is validated by applying the analytical expression to different biphasic composite structures with different...
The systropic sphere is a spherical scatterer whose axes of anisotropy are defined by spherical coordinates. This contribution discusses the electrostatic scattering from a systropic sphere with extreme material parameters. The permittivity divides into three component in the spherical coordinates. Larger component values produce more polarizability, but there is a limit to the increase of the polarizability...
This presentation focuses on the perfect analogy between the Maxwell Garnett mixing formula and the effective polarizability of a piecewise homogeneous dielectric sphere. Due to this correspondence, it is possible to transfer results between these domains, from extended mixtures to properties of single-particle scattering, and vice versa. As examples, we discuss the bounds for the effective parameters,...
To find the electrostatic solution of a radially uniaxially anisotropic sphere in a constant external field is fairly straightforward. However, the resulting quasistatic polarizability exhibits many interesting properties including singularities and dubious emergent losses. By removing the origin and adding small losses, it turns out that the solution is valid in a certain limiting sense. Without...
We study the occurrence of the so-called anti-resonance in the material parameters (permittivity, permeability) characterizing the electromagnetic response of a composite material slab. The material parameters are retrieved using the well-known reflection/transmission method. As many previous works have either claimed or assumed that the antiresonance is an effect caused by the periodicity of the...
Multilayered wire-grid polarizers (WGP) find application as low-reflection polarizers in projection-type liquid crystal display devices. We describe a design method for multilayered WGPs based on a monochromatic recursive convolution finite-difference time-domain algorithm. The goal is to identify suitable materials and thicknesses for the additional layers needed to lower the reflectivity.
We present a method aimed at reducing uncertainties and instabilities when characterizing materials in waveguide setups. The S-parameters for a rectangular waveguide loaded with a rectangular sample block are measured for three different sample orientations, and the corresponding geometries are modeled in a finite element program, taking any material parameters as input. The material parameters of...
The electromagnetic modelling of cavity resonators loaded with dielectric material is important with respect to corresponding material measurements. In this paper, a variational technique is employed to determine the complex resonant frequencies of the loaded cavity resonator. Inhomogeneous impedance boundary conditions are considered to take the effects of lossy walls and the filling hole of the...
In this paper the scattering characteristics are calculated with the technique based on the volume integral equations for polarization currents. A study of electromagnetic field interaction with the 3D lattice dielectric structure involved defect layer and gain material is performed in this paper. An effect of gain material parameters on the amplification level of the structure is investigated. Distributions...
An improved TR (transmission/reflection) method for measuring the complex permittivity of powder and liquid samples with slabline is provided in this paper. The method can afford quite high accurate measurement results without singularities, and broaden the operating frequency band to 2–18GHz. Some experiments are carried out to verify the feasibility of the improved TR method for permittivity measurement...
Conventionally, techniques based on micro strip and rectangular wave guides have been utilized for determining the permittivity of materials, however these techniques require elaborated procedures due to quasi-Transversal Electromagnetic mode (quasi-TEM) and Transversal Electric/Transversal Magnetic (TE/TM) propagation modes. In this paper, a new technique based on a parallel-plate wave guide concept...
We have developed sensors suited for the measuring of inclination and acceleration with a very high sensitivity. Data can be extracted by means of the capacitive transducing effect. A single sided interdigital electrode arrangement on a solid was used. Changes of the capacity due to mechanical forces can be detected by changes in the permittivity above the electrodes only in this case. Changes of...
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