An application of a mode dielectric resonator is described for precise measurements complex permittivity and the thermal effects on isotropic materials. The Rayleigh-Ritz technique was employed to find rigorous relationship between permittivity, resonant frequency, dimensions structure, with relative computational accuracy less than . influence conductor loss its temperature dependence taken into account in tangent evaluation. Complex permittivities several materials, including cross-linked...

Overview of frequency domain measurement techniques the complex permittivity at microwave frequencies is presented. The methods are divided into two categories: resonant and non-resonant ones. In first category several discussed such as cavity resonator techniques, dielectric open resonators for non-destructive testing. general theory measurements different materials in structures presented showing mathematical background, sources uncertainties theoretical experimental limits. Methods...

We demonstrate the growth of high quality graphene layers by chemical vapor deposition (CVD) on insulating and conductive SiC substrates. This method provides key advantages over well-developed epitaxial Si sublimation that has been known for decades.(1) CVD is much less sensitive to surface defects resulting in electron mobilities ∼1800 cm2/(V s) enables controlled synthesis a determined number with defined doping level. The evidenced unique combination angle-resolved photoemission...

Whispering gallery modes were used for very accurate permittivity and dielectric loss measurements of ultralow isotropic uniaxially anisotropic single crystals. Several materials including sapphire, YAG, quartz, SrLaAlO4 measured. The total absolute uncertainty in the real part tensor components was estimated to be ±0.1%, limited principally by sample dimensions. Imaginary parts permittivities measured with uncertainties about 10%, accuracy Q-factor whispering modes. It has been observed...

In this paper, we present complex permittivity data at microwave frequencies (approximately 10 GHz) for many common plastics over a temperature range of 122 to 375 K. The measurements were made with TE/sub 01/spl delta// dielectric resonator placed inside an environmental chamber. Data are presented the following materials: acrylonitrile butadiene styrene, polytetrafluoroethylene, cross-linked polystyrene, tetrafluorethylene-perfluorpropylene, polypropylene, polysulfone,...

A dielectric resonator technique has been used for measurements of the permittivity and loss tangent single-crystal substrates in temperature range 20-300 K at microwave frequencies. Application superconducting films made it possible to determine tangents about 5/spl times/10/sup -7/ 20 K. Two tensor components uniaxially anisotropic samples were measured. Generally, same material by different manufacturers or processes save significantly losses, although they have essentially...

Whispering-gallery modes are used for very accurate permittivity, dielectric loss, and temperature coefficient of permittivity measurements both isotropic uniaxially anisotropic materials. The relationship between resonant frequencies, dimensions the structure, sample under test is calculated with a radial mode-matching technique. relative accuracy these computations better then 10/sup -4/. influence conductor losses on loss tangent determination treated whispering-gallery-mode TE/sub 01/spl...

Measurements on low-loss materials using closed and open cavity resonators, dielectric resonator methods are presented. Results indicate that consistent measurement results can be obtained with a number of well-characterized fixtures. Uncertainties associated each method addressed. also were performed used in previous intercomparisons.

The complex permittivity and resistivity of float-zone high-resistivity silicon were measured at microwave frequencies for temperatures from 10 up to 400 K employing dielectric-resonator composite techniques.At below 25 K, where all free carriers are frozen out, loss-tangent values the order 2 4 measured, suggesting existence hopping conductivity or surface charge carrier in this temperature range.Use a dielectricresonator technique enabled measurement materials having higher dielectric...

A sapphire dielectric resonator with a copper cylindrical shield and two endplates replaced by high-temperature superconducting (HTS) layers was used for very accurate surface resistance measurements on laser-ablated YBCO films. system using the TE/sub 011/ mode has resonant frequency of about 18.1 GHz parasitic-loss Q factor 120000. It allows 10 mm*10 mm samples to be measured sensitivity +or-30 mu Omega . Individual can somewhat lower accuracy. Using larger HTS samples, one reduce...

Single postdielectric resonators operating on their quasi TE011 modes were used for the measurement of surface resistance and conductivity graphene films grown semi-insulating SiC substrates. With this technique was measured with an uncertainty ±5% evaluated equal to in determining film thickness. The room temperature proved be range 5×106 6.4×106 S/m.

Contactless methods of conductivity measurement are becoming increasingly important due to the progress being made in materials technology and development new intended for use electronics industry, including graphene, GaN SiC. Despite fact that they conducting materials, some them, like SiC, cannot be measured with conventional four-point probe technique. techniques offer fast non-destructive measure such materials. Selection appropriate method from available makes it possible over a...

The dielectric properties of a single crystal rutile (TiO2) resonator have been measured using whispering gallery modes. Q factors and resonant frequencies were from 300 to 10 K. as high 104, 105, 107 obtained at 300, 80, K, respectively. Using the mode technique we determined accurately loss tangent constant monocrystalline much more sensitive measurements than previously reported. We show that exhibits anisotropy in both permittivity over range

Complex permittivity of Polytetrafluoroethylene (PTFE), Polypropylene (PP), Polyethylene (PE) and cross-linked Polystyrene (Rexolite), has been measured at frequency range from 5 GHz to 50 GHz. Measurements have performed in two cylindrical cavities employing several quasi <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}_{0 \mathrm{mn}}$</tex-math></inline-formula> modes excited samples under...

A novel approach to the measurement of complex permittivity low-loss dielectric materials with aid an open Fabry-Pérot resonator concave Gaussian mirrors is presented in this paper. For that purpose, a new scalar 1-D layered electromagnetic (EM) model proposed. The takes advantage Cartesian-to-Gaussian coordinate transformation and axisymmetrical properties TEM modes interest. There are several advantages proposed approach. first use instead spherical ones, which better fit shape wavefronts....

The split dielectric resonator technique makes it possible to measure the real part of permittivity isotropic materials for a very broad range and loss tangents in from 10⁻⁴ 10⁻¹ with high accuracy. For uniaxially anisotropic materials, method permits measurement tangent plane parallel sample bottoms. Additional measurements using re-entrant cavity enable determination perpendicular this plane.

The Rayleigh-Ritz method and the finite element nongenerating spurious solutions are employed for analysis of whispering gallery modes (WGMs) in cylindrical single-crystal anisotropic dielectric resonators. These methods allow accurate computation resonant frequencies, Q-factors (depending on conductor losses), electromagnetic field distributions all WGMs presence additional elements like metal shields, MIC substrate, or supports. Different families studied both theoretically experimentally....

Complementary single- and split-post dielectric- resonator techniques were used for contactless absolute resistivity measurements of semiconductor wafers onwafer mapping in the range 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> to xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> Omega ldr cm. Uncertainties employing both are 2%-4%. Permittivities high-resistivity semiconductors measured with uncertainties approximately 0.5%....

A Fabry–Pérot open resonator is a tool dedicated to broadband accurate microwave and mm-wave characterization of dielectric sheets. It has been applied in this paper the measurement constant loss tangent various types commonly used materials, such as semiconductors, electronic substrates, glasses, plastics, 20–110 GHz range. The obtained results are good agreement with literature data, which are, however, often available only at discrete frequencies, thus making it difficult recognize...

The Galerkin-Rayleigh-Ritz method is applied for computing the first few lowest resonant frequencies of cylindrical anisotropic resonators in a cavity. are allowed to have gyromagnetic and uniaxial dielectric anisotropy with respect z-axis cylinder. Results computations compared exact solutions many simple structures results experiments more complicated structures, good agreement. A new measuring permeability tensor components presented. utilizes two parallel-plate operating HE/sup +/-//sub...

In this Letter, we report on measurements of the complex permittivity highly anisotropic nematic liquid crystals at microwave frequencies as a function AC bias voltage. Permittivity have been performed by split post dielectric resonator technique. The experiments shown that when voltage increases from 0 to 8 V, real part these changes up 28%. tunability and relatively low losses observed in crystal mixtures mean they are ideal materials for design tunable components.

Abstract Numerical solutions of coupled Maxwell and Landau-Lifshitz-Gilbert equations for a magnetized yttrium iron garnet (YIG) sphere acting as one-stage filter are presented. The is analysed using finite-difference time-domain technique. Contrary to the state art, study shows that maximum electromagnetic power transmission through YIG occurs at frequency magnetic plasmon resonance with effective permeability gyromagnetic medium μ r ≈ −2, not ferromagnetic frequency. Such new understanding...