Journal articles: 'Dielectic modes'

1

Eliseeva, D. A., and S. O. Safonov. "Analysis of Degradation Mechanisms of Gate Dielectrics Based on SiO2 in MOS Transistors." Proceedings of Universities. ELECTRONICS 25, no. 6 (December 2020): 517–24. http://dx.doi.org/10.24151/1561-5405-2020-25-6-517-524.

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Nowadays, the developed mathematical models, describing the degradation mechanism of the gate dielectric, permit to determine the value of the operating time to failure of a device depending on its internal properties and operating conditions. These models significantly reduce the time and material required for performing testing and processing of large amounts of experimental data. In the paper the gate dielectric gates based on SiO in n -and p -channel MOS transistors have been studied. It has been found that under the impact of the electric field the degradation of the gate dielectric with 5.3 nm thickness most likely occurs according to the thermochemical model ( E -model) and in case with 7 nm thickness dielectric- in accordance with the anode hole injection model (1/ E -model). The coefficients have been calculated and the analysis of the mathematical models, permitting to determine the service life gate dielectrics based on SiO with 7 nm thickness in n - and p -channel MOS transistors for different values, of their area, operating voltage and temperature, has been performed. This study can serve as a method for monitoring and determining the quality of the gate dielectrics of manufactured MOS transistors.

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MARACHEVSKY, VALERY N. "CASIMIR ENERGY AND REALISTIC MODEL OF DILUTE DIELECTRIC BALL." Modern Physics Letters A 16, no. 15 (May 20, 2001): 1007–16. http://dx.doi.org/10.1142/s0217732301004078.

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The Casimir energy of a dilute homogeneous nonmagnetic dielectric ball at zero temperature is derived analytically for the first time for an arbitrary physically possible frequency dispersion of dielectric permittivity ε(iω). A microscopic model of dielectrics is considered, divergences are absent in calculations because an average interatomic distance λ is a physical cutoff in the theory. This fact has been overlooked earlier, which led to divergences in various macroscopic approaches to the Casimir energy of connected dielectrics.

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Liu, Di-Fan, Qi-Kun Feng, Yong-Xin Zhang, Shao-Long Zhong, and Zhi-Min Dang. "Prediction of high-temperature polymer dielectrics using a Bayesian molecular design model." Journal of Applied Physics 132, no. 1 (July 7, 2022): 014901. http://dx.doi.org/10.1063/5.0094746.

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Machine learning has shown its great potential in the accelerated discovery of advanced materials in the field of computational molecular design. High-temperature polymer dielectrics are urgently required with the emerging applications of energy-storage dielectric film capacitors under high-temperature conditions. Here, we demonstrate the successful prediction of polymers with a high dielectric constant ( ɛ) and high glass transition temperature ( Tg) using a Bayesian molecular design model. The model is trained on a joint data set containing 382 computed ɛ values using density functional perturbation theory and experimentally measured Tg values of ∼7000 polymers to build relative quantitative structure–property relationships and identify the promising polymers with specific desired range of dielectric constant and glass transition temperature. From the hypothetical polymer candidates, ten promising polymers are proposed based on their predicted properties and synthetic accessibility score for high-temperature dielectric film capacitors’ application. Moreover, 250k novel polymer structures are generated with the model to support future polymer informatics research. This work contributes to the successful prediction of high-temperature polymer dielectrics using machine learning models.

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Dmitrikov, Vladimir F., and Dmitry V. Shushpanov. "Equivalent circuit of a dielectric in a wide frequency range (0 Hz – 500 MHz)." Physics of Wave Processes and Radio Systems 25, no. 3 (September 29, 2022): 43–57. http://dx.doi.org/10.18469/1810-3189.2022.25.3.43-57.

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Based on the measured impedance of the dielectrics an equivalent high frequency (0 Hz - 500 MHz) circuit model was built. The equivalent circuit model was built taking into account the physical processes occurring in the dielectric. The attempt explaining why the frequency characteristics (modulus and phase) of the dielectric complex impedance have such a character in a wide frequency band (up to 500 MHz) was made. It was shown that for constructing an equivalent circuit model (structure and parameters), measuring only the dielectrics resistance modulus is not enough. It is also necessary to measure the phase of the dielectric complex resistance, which is ignored in many works on the synthesis of an e dielectric equivalent circuit.

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Wagaye, Gebremedhn Wubet. "Performance Investigation of Coaxial Cable with Transmission Line Parameters Based on Lossy Dielectric Medium." Indonesian Journal of Electrical Engineering and Computer Science 11, no. 2 (August 1, 2018): 424. http://dx.doi.org/10.11591/ijeecs.v11.i2.pp424-428.

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This paper presents the analysis of high performance for coaxial cable with transmission line parameters. The modeling for performance of coaxial cable contains many parameters, in this paper will discuss the more effective parameter is the type of dielectric mediums. This analysis of the performance related to dielectric mediums with respect to dielectric losses and its effect upon cable properties, dielectrics versus characteristic impedance, and the attenuation in the coaxial line for different dielectrics. The analysis depends on a simple mathematical model for coaxial cables to test the influence of the insulators (Dielectrics) performance.

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Fimin, A. V., E. A. Pecherskaya, O. A. Timokhina, V. S. Aleksandrov, A. V. Volik, and A. E. Shepeleva. "Investigation of the dielectric fatigue on the example of lead titanate films PbTiO₃." Journal of Physics: Conference Series 2086, no. 1 (December 1, 2021): 012179. http://dx.doi.org/10.1088/1742-6596/2086/1/012179.

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Abstract The phenomenon of dielectric fatigue of active dielectrics, which consists in a decrease in the residual polarization depending on the number of switching cycles, is researched. A model of the dependence of the residual polarization of ferroelectric materials on the number of switching cycles is proposed. The model is based on piecewise - linear approximation of the results of measurements of the hysteresis loops of thin films PbTiO3 at a temperature T = 470 (°C), the electric field strength E = 100 (kV/cm). The developed model was used in the development of a technique for studying dielectric fatigue, depending on different modes of material switching.

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Kalytka, Valeriy, Felix Bulatbayev, Yelena Neshina, Yekaterina Bilichenko, Arkadiy Bilichenko, Aleksandr Bashirov, Yelena Sidorina, Yelena Naboko, Nurbol Malikov, and Yelena Senina. "Theoretical Studies of Nonlinear Relaxation Electrophysical Phenomena in Dielectrics with Ionic–Molecular Chemical Bonds in a Wide Range of Fields and Temperatures." Applied Sciences 12, no. 13 (June 28, 2022): 6555. http://dx.doi.org/10.3390/app12136555.

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This paper is devoted to the development of generalized (for a wide range of fields (100 kV/m–1000 MV/m) and temperatures (0–1500 K) in the radio frequency range (1 kHz–500 MHz)) methods for the theoretical investigation of the physical mechanism of nonlinear kinetic phenomena during the establishment of the relaxation polarization, due to the diffusion motion of the main charge carriers in dielectrics with ionic–molecular chemical bonds (hydrogen-bonded crystals (HBC), including layered silicates, crystalline hydrates and corundum–zirconium ceramics (CZC), etc.) in an electric field. The influence of the nonlinearities equations of the initial phenomenological model of dielectric relaxation (in HBC-proton relaxation) on the mechanism for the formation of volume–charge polarization in solid dielectrics is analyzed. The solutions for the nonlinear kinetic Fokker–Planck equation, together with the Poisson equation, for the model of blocked electrodes are built in an infinite approximation (including all orders k of smallness without dimensional parameters) of perturbation theory for an arbitrary order r of the frequency harmonic of an alternating external polarizing field. It has been established that the polarization nonlinearities in ion-molecular dielectrics, already detected at the fundamental frequency, are interpreted in the mathematical model (for the first time in this work) as interactions of the relaxation modes of the volume charge density calculated on different orders of spatial Fourier harmonics. At the fundamental frequency of the field, an analytical generalized expression is written for complex dielectric permittivity (CDP), which is expressed analytically in terms of special relaxation parameters, which are quite complex real functions in the fields of frequency and temperature. The theoretical CDP and the dielectric loss tangent spectra studied depend on the nature of the relaxation processes in the selected temperature range (Maxwell and diffusion relaxation; thermally activated and tunneling relaxation), which is relevant from the point of view of choosing exact calculation formulas when analyzing the optimal operating modes of functional elements (based on dielectrics and their composites) for circuits of instrumentation, radio engineering and power equipment in real industrial production.

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Rodríguez-Serna, Johnatan M., Ricardo Albarracín-Sánchez, and Isabel Carrillo. "An Improved Physical-Stochastic Model for Simulating Electrical Tree Propagation in Solid Polymeric Dielectrics." Polymers 12, no. 8 (August 7, 2020): 1768. http://dx.doi.org/10.3390/polym12081768.

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The dielectric breakdown of solid polymeric materials is due to the inception and propagation of electrical trees inside them. The remaining useful life of the solid dielectrics could be determined using propagation simulations correlated with non-intrusive measurements such as partial discharges (PD). This paper presents a brief review of the different models for simulating electrical tree propagation in solid dielectrics. A novel improved physical-stochastic model is proposed, which allows quantitatively and qualitatively analyzing the electrical tree propagation process in polymeric dielectrics. Simulation results exhibit good agreement with measurements presented in the literature. It is concluded that the model allows adequately predicting the tree propagation behavior and additional experimental analyses are required in order to improve the model accuracy.

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9

Yu, Hong Tao, Wen Bo Zhang, Jing Song Liu, Lin Hong Cao, and Han Xing Liu. "A Simple Model for Predicating Dielectric Constant of CaCu₃Ti₄O₁₂-SrTiO₃ Composite Ceramics." Materials Science Forum 689 (June 2011): 24–28. http://dx.doi.org/10.4028/www.scientific.net/msf.689.24.

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In this work, we have proposed a simple model to predicte the dielectric constant of CaCu3Ti4O12-SrTiO3composite ceramics. The model has been established based on the analysis of composition and microstructure. Two different compositions in the composite ceramics correspond to two different grain sizes, large for CaCu3Ti4O12, and small for SrTiO3, which has been identified by the x-ray diffraction, the scanning electron microscope and the energy spectrum analysis. All specimens have been assumed to be the barrier layer dielectrics in the model, according to the complex impedance spectra. The dielectric constant of serial, parallel, and logarithmic mixture models has been discussed. Compared with the experimental results, the model shows the similar variation tendency as SrTiO3content increases.

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Denisenko, D. V., and V. V. Radchenko. "Quasistasic modeling of edge fields in planar resonators." Issues of radio electronics 49, no. 5 (July 5, 2020): 64–70. http://dx.doi.org/10.21778/2218-5453-2020-5-64-70.

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This paper discusses quasistatic waveguide model for planar resonator placed in multilayer dielectic media, which do not use effective parameters such as effective width of resonator and effective dielectric constant. It allows to use waveguide model in new approach. Edge field is modeled by inclusion of LC-lumped element circuit where values of inductances and capacitances we determined from the solving of electrostatic Laplace equation by the method of moment using the three-dimensional Green function for multilayer dielectric media. A computational experiment showed that the proposed model is effective in modeling planar resonators of complex shape and requires low computational resources.

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11

MARACHEVSKY, VALERY N. "CASIMIR ENERGY OF A DILUTE DISPERSIVE DIELECTRIC BALL: REALISTIC MICROSCOPIC MODEL." International Journal of Modern Physics A 17, no. 06n07 (March 20, 2002): 786–89. http://dx.doi.org/10.1142/s0217751x0201011x.

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The Casimir energy of a dilute homogeneous nonmagnetic dielectric ball at zero temperature is derived analytically within a microscopic realistic model of dielectrics for an arbitrary physically possible frequency dispersion of dielectric permittivity ε(iω). Divergences are absent in calculations, a minimum interatomic distance λ is a physical cut-off. Casimir surface force is proved to be a attractive. A physical definition of the Casimir energy is discussed.

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Phillips, Jonathan. "Theoretical and experimental basis for the super dielectric model of dielectric materials." Physics Essays 33, no. 3 (September 11, 2020): 306–18. http://dx.doi.org/10.4006/0836-1398-33.3.306.

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Two theories of the fields generated by charges on parallel plate capacitors, the standard model (SM) found in virtually all text books and the recently proposed super dielectric material-theory (SDM-Theory), are described, and contrasted, in terms of theory and experimentally tested predictions. Only the SDM-Theory model is found to be consistent with thermodynamics, basic field theory, and experimental results. According to the SM, dielectrics in the volume between the electrodes of a parallel plate capacitor store the energy in a capacitor in the form of greatly, relative to the no dielectric case, increased electric field strength. This model is shown to be inconsistent with path independent changes in state property (e.g., voltage), and predicts, incorrectly, that dielectric material outside the volume between the electrodes will have no effect on any measurable properties such as capacitance and energy density. In contrast, according to SDM-Theory, a theory shown to be consistent with path independent changes in state properties, as well as “conservative field theory,” the increased stored energy in the presence of dielectrics is not associated with energy in fields, but rather it is due to the “extra” charges stored on the electrodes. The extra charge is required to create a given net field in the presence of a dielectric. Indeed, according to SDM-Theory, the effect of dielectric material, because its polarization is opposite to the electrodes, reduces the net field at all points in space, including within the volume of the dielectric. This is the absolute opposite of the “action” of a dielectric predicated by the SM. In the SDM-Theory, at a given capacitor voltage, virtually identical net fields exist with and without a dielectric, but the capacitance (amount of stored charge) and stored energy, a linear function of the amount of stored charge, of the latter configuration can be many orders of magnitude greater. Moreover, SDM-Theory predicts, consistent with recent observations, that dielectric material external to the volume between electrodes should be nearly as effective at increasing capacitance, etc., as the same dielectric material between the electrodes.

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13

Gkortsas, Vasileios-Marios, Lalitha Venkataramanan, Kamilla Fellah, David Ramsdell, Chang-Yu Hou, and Nikita Seleznev. "Comparison of different dielectric models to calculate water saturation and estimate textural parameters in partially saturated cores." GEOPHYSICS 83, no. 5 (September 1, 2018): E303—E318. http://dx.doi.org/10.1190/geo2018-0100.1.

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Accurate estimation of water saturation is central in predicting capillary pressure and relative permeability, under special core analysis in the laboratory. We have explored the use of dielectric measurements at different frequencies to estimate water saturation. In addition to water saturation, dielectric measurements are sensitive to the distribution of water and oil in a porous system, reflected by the apparent cementation factor [Formula: see text], which describes the water phase tortuosity. We have performed an experimental study to benchmark water saturation from dielectric measurements on eight carbonate cores and estimated their cementation exponent [Formula: see text] and saturation exponent [Formula: see text] in Archie’s equation from dielectric data. All cores went through a series of drainage/imbibition steps, creating varying saturations of brine/fluorocarbon. Fluorocarbon was chosen because it is invisible to proton nuclear magnetic resonance (NMR). Therefore,NMR porosity represents only the water-filled porosity and can be used to benchmark dielectric water-filled porosity. Three dielectric models were used for the comparison of the dielectric water-filled porosity with the one from NMR, i.e., the complex refractive index model (CRIM), bimodal model, and Stroud-Milton-De (SMD) model, and very good agreement of 1.5 porosity units on average is found. Despite its simplicity, CRIM predicted well the water-filled porosity in this experiment. However, it cannot provide information about the texture, which is captured by bimodal and SMD models. We also estimated [Formula: see text] and [Formula: see text] based on [Formula: see text] found from bimodal and SMD models, and good agreement with [Formula: see text] from resistivity data was shown. This is the first time to our knowledge that such a rich set of dielectric and NMR measurements was acquired at different saturation stages in a surface laboratory. This study is useful in benchmarking the water saturation from dielectrics, comparing different dielectric models, and demonstrating feasibility of estimating textural parameters.

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Jung, Hakkee. "Analytical models of threshold voltage and drain induced barrier lowering in junctionless cylindrical surrounding gate (JLCSG) MOSFET using stacked high-k oxide." AIMS Electronics and Electrical Engineering 6, no. 2 (2022): 108–23. http://dx.doi.org/10.3934/electreng.2022007.

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<abstract> We proposed the analytical models to analyze shifts in threshold voltage and drain induced barrier lowering (DIBL) when the stacked SiO2/high-<italic>k</italic> dielectric was used as the oxide film of Junctionless Cylindrical Surrounding Gate (JLCSG) MOSFET. As a result of comparing the results of the presented model with those of TCAD, it was a good fit, thus proving the validity of the presented model. It could be found that the threshold voltage increased, but DIBL decreased by these models as the high-<italic>k</italic> dielectric constant increased. However, the shifts of threshold voltage and DIBL significantly decreased as the high-<italic>k</italic> dielectric constant increased. As for the degree of reduction, the channel length had a greater effect than the thickness of the high-<italic>k</italic> dielectric, and the shifts of threshold voltage and DIBL were kept almost constant when the high-<italic>k</italic> dielectric constant was 20 or higher. Therefore, the use of dielectrics such as HfO2/ZrO2, La2O3, and TiO2 with a dielectric constant of 20 or more for stacked oxide will be advantageous in reducing the short channel effect. In conclusion, these models were able to sufficiently analyze the threshold voltage and DIBL. </abstract>

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Petzelt, Jan. "Infrared and THz spectroscopy of nanostructured dielectrics." Processing and Application of Ceramics 3, no. 3 (2009): 145–55. http://dx.doi.org/10.2298/pac0903145p.

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Results achieved using the infrared/THz spectroscopy of various inhomogeneous dielectrics in the Department of Dielectrics, Institute of Physics, Prague, during the last decade are briefly reviewed. The discussion concerns high-permittivity ceramics with inevitable low-permittivity dead layers along the grain boundaries, relaxor ferroelectrics with highly anisotropic polar nano-regions, classical matrix-type composites, core-shell composites, filled nanoporous glasses, polycrystalline and epitaxial thin films, heterostructures and superlattices on dielectric substrates. The analysis using models based on the effective medium approach is discussed. The importance of depolarizing field and of the percolation of components on the effective ac dielectric response and the excitations contributing to it are emphasized. .

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Shalimova, M. B., V. S. Afanaskov, and E. N. Khavdey. "MECHANISMS OF DEGRADATION OF ELECTROPHYSICAL CHARACTERISTICS OF MOS-STRUCTURES WITH HIGH-K DIELECTRICS." Vestnik of Samara University. Natural Science Series 19, no. 3 (June 1, 2017): 107–19. http://dx.doi.org/10.18287/2541-7525-2013-19-3-107-119.

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Results of study of the processes of change of electrophysical characteristics are presented at various operating modes of MOS-structures and the analysis of the most probable mechanisms of degradation of structures was spent. The gate dielectric was made from rare-earth oxides (high-k dielectrics). The estimation of influence of electric field and temperature on change of a charge of investigated structures was spent, the value of energetically density of states on the interface dielectric — semiconductor was defined.

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Novkovski, Nenad. "Physical modeling of electrical and dielectric properties of high-k ta2o5 based MOS capacitors on silicon." Facta universitatis - series: Electronics and Energetics 27, no. 2 (2014): 259–73. http://dx.doi.org/10.2298/fuee1402259n.

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In this paper we present an integral physical model for describing electrical and dielectric properties of MOS structures containing dielectric stack composed of a high-k dielectric (with emphasize on pure and doped Ta2O5) and an interfacial silicon dioxide or silicon oxynitride layer. Based on the model, an equivalent circuit of the structure is proposed. Validity of the model was demonstrated for structures containing different metal gates (Al, Au, Pt, W, TiN, Mo) and different Ta2O5 based high-k dielectrics, grown of bare or nitrided silicon substrates. The model describes very well the I-V characteristics of the considered structures, as well as frequency dependence of the capacitance in accumulation. Stress-induced leakage currents are also effectively analyzed by the use of the model.

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Lu, Feng Ming, Jiang Shao, Xiao Yu Liu, and Xing Hao Wang. "Research on TDDB Effect in High-k Materials." Advanced Materials Research 548 (July 2012): 203–8. http://dx.doi.org/10.4028/www.scientific.net/amr.548.203.

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With continual scaling of ICs, the thickness of gate oxide becomes thinner and thinner which affects the reliability of semiconductor device greatly. The mechanism of time-dependent dielectric breakdown (TDDB) was analyzed. Six mathematical models of TDDB which were divided according to the position of defects and the physical property of charged particles were discussed. Then the dielectric breakdown characteristic of high k dielectrics and the relationships between the breakdown electric field, field acceleration parameter and dielectric constant were analyzed in detail. Finally, the relationships and mathematical models were verified by experimental data which provided theoretical basis for the choosing and use of high k materials.

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DARYANOOSH, S., and H. MEHDIAN. "Dispersion relation for azimuthal electromagnetic surface waves on a magnetized annular plasma in a metal waveguide with coaxial anisotropic dielectric inner coating." Journal of Plasma Physics 73, no. 6 (December 2007): 839–55. http://dx.doi.org/10.1017/s0022377807006356.

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AbstractThe dispersion relation of azimuthal electromagnetic surface waves on a magnetized annular plasma surrounded by a metallic cylindrical coaxial anisotropic dielectric lined waveguide is obtained. The thickness of the dielectric and its location in the waveguide are studied with respect to their effects on the number of spectra observed. The graphs of frequency spectra against the ratio of radii of the annular plasma and η = ωpe/Ωe are plotted. Finally, surface E-modes for coaxial anisotropic and isotropic dielectrics have been investigated.

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Gyure, Mark F., and Paul D. Beale. "Dielectric breakdown in continuous models of metal-loaded dielectrics." Physical Review B 46, no. 7 (August 15, 1992): 3736–46. http://dx.doi.org/10.1103/physrevb.46.3736.

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Li, Liyang, Jun Wang, Hua Ma, Jiafu Wang, Hongliang Du, and Shaobo Qu. "Polarization insensitive metamaterial absorber based on E-shaped all-dielectric structure." Journal of Advanced Dielectrics 05, no. 01 (March 2015): 1550009. http://dx.doi.org/10.1142/s2010135x15500095.

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In this paper, we designed a metamaterial absorber performed in microwave frequency band. This absorber is composed of E-shaped dielectrics which are arranged along different directions. The E-shaped all-dielectric structure is made of microwave ceramics with high permittivity and low loss. Within about 1 GHz frequency band, more than 86% absorption efficiency was observed for this metamaterial absorber. This absorber is polarization insensitive and is stable for incident angles. It is figured out that the polarization insensitive absorption is caused by the nearly located varied resonant modes which are excited by the E-shaped all-dielectric resonators with the same size but in the different direction. The E-shaped dielectric absorber contains intensive resonant points. Our research work paves a way for designing all-dielectric absorber.

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Kanwal, Samra, Chun Yun Kee, Samuel Y. W. Low, Muhammad Zubair, and L. K. Ang. "Capacitance for fractal-like disordered dielectric slab." Journal of Applied Physics 132, no. 2 (July 14, 2022): 024104. http://dx.doi.org/10.1063/5.0100159.

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In this paper, we model a heterogeneous dielectric medium exhibiting fractal geometry or disordered random structures by applying non-integer dimensions to determine its capacitance between two parallel plates. The capacitance depends on the fractional dimensions of the fractal or disordered dielectric slab, which may be obtained from the theoretical fractal dimension or box-counting method. The findings are verified by CST Studio Suite (Electromagnetic field simulation software), experimental measurements, and the equivalent capacitance method. Five common types of fractals (Cantor bars/plates, Sierpinski carpet, Sierpinski triangle, Haferman carpet, and Menger sponge) and random structures are tested with good agreement. There is also an effective gain of capacitance in using less amount of dielectric materials, which may be useful in material-savings of dielectrics. This research shows a useful tool in modeling the capacitance of heterogeneous materials, where fractals and disordered structures may be commonly encountered in organic materials and any dielectrics where precision and fabrication are not perfect.

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Hao, Tian, and Yuanze Xu. "DIELECTRIC EVIDENCE FOR THE MATERIAL DESIGN OF ER FLUIDS." International Journal of Modern Physics B 10, no. 23n24 (October 30, 1996): 2885–93. http://dx.doi.org/10.1142/s0217979296001331.

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The dielectric and electrorheological measurements of anhydrous ER fluids based upon oxidized polyacrylonitrile and zeolite under AC electric field are described It was found that the yield strength was not only determined by dielectric constant of suspensions, but also by dielectric loss. The formulation based on Wagner model, which describes the polarization of heterogeneous dielectrics, was employed to predict the yield stress as a function of electric frequency. The good agreement between experimental and theoretical predictions indicated that conductivity of the dispersed particle and the dielectric constants of ER suspension are decisive factors in the design of ER fluids. The way of material design is discussed concerning working frequency, rate and temperature ranges

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Susarla, Sandhya, Thierry Tsafack, Peter Samora Owuor, Anand B. Puthirath, Jordan A. Hachtel, Ganguli Babu, Amey Apte, et al. "High-K dielectric sulfur-selenium alloys." Science Advances 5, no. 5 (May 2019): eaau9785. http://dx.doi.org/10.1126/sciadv.aau9785.

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Upcoming advancements in flexible technology require mechanically compliant dielectric materials. Current dielectrics have either high dielectric constant, K (e.g., metal oxides) or good flexibility (e.g., polymers). Here, we achieve a golden mean of these properties and obtain a lightweight, viscoelastic, high-K dielectric material by combining two nonpolar, brittle constituents, namely, sulfur (S) and selenium (Se). This S-Se alloy retains polymer-like mechanical flexibility along with a dielectric strength (40 kV/mm) and a high dielectric constant (K = 74 at 1 MHz) similar to those of established metal oxides. Our theoretical model suggests that the principal reason is the strong dipole moment generated due to the unique structural orientation between S and Se atoms. The S-Se alloys can bridge the chasm between mechanically soft and high-K dielectric materials toward several flexible device applications.

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Gall, L. N., and A. G. Kouzmin. "Creeping Discharge Mass Spectrometry: A New Method for Elemental Analysis of Dielectrics." European Journal of Mass Spectrometry 8, no. 3 (June 2002): 207–12. http://dx.doi.org/10.1255/ejms.493.

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The creeping discharge (CD), a special kind of surface discharge, is proposed as a method of ionization in mass spectrometry for elemental analysis of dielectrics. Characteristic features of creeping discharge ionization mass spectra of dielectric samples were studied. An yttrium oxide standard sample and dielectrics of high electric strength were successfully analyzed. The results of analysis of the ion charge state in creeping discharge are presented. A theoretical model of creeping discharge ionization is offered.

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Hraniak, Valerii, and Oleksandr Kozhushko. "EVALUATION OF SYSTEMATIC ERRORS OF STRIP ASYMMETRIC HUMIDITY SENSOR." ENGINEERING, ENERGY, TRANSPORT AIC, no. 1(116) (April 29, 2022): 164–69. http://dx.doi.org/10.37128/2520-6168-2022-1-19.

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The methodical estimation of the methodical component of the error arising at measurement of humidity of heterogeneous dispersed dielectrics by the band asymmetric sensor is carried out. In the process of evaluation it was shown that the most significant component of methodological error occurs due to changes in temperature and frequency of the information wave. Temperature-dependent values included in the mathematical model of the band asymmetric humidity sensor are: relative dielectric constant of the substrate dielectric and the object of control, length and width of the central conductor, substrate dielectric thickness. The dielectric constant of the dielectric of the object of control depends on the frequency of the information wave, and this parameter is directly included in the coefficients of the sensor conversion equation. The results of the research showed that in the process of measuring the conversion of humidity in the band asymmetric sensor there is a methodological component of the error associated with changes in temperature and instability of the frequency of the information wave. To ensure a frequency error at a level not exceeding 0.5%, the error of instability of the frequency of the information wave when converting humidity into the output amplitude of the information wave should not exceed ± 3 kHz, provided by existing RF generators. It is advisable to remove the temperature component of the error using the method of correction. The mathematical model of band asymmetric measurement of moisture conversion of heterogeneous dispersed dielectrics in the high-frequency region was also improved.

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Min, Daomin, Chenyu Yan, Rui Mi, Chao Ma, Yin Huang, Shengtao Li, Qingzhou Wu, and Zhaoliang Xing. "Carrier Transport and Molecular Displacement Modulated dc Electrical Breakdown of Polypropylene Nanocomposites." Polymers 10, no. 11 (October 30, 2018): 1207. http://dx.doi.org/10.3390/polym10111207.

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Dielectric energy storage capacitors have advantages such as ultra-high power density, extremely fast charge and discharge speed, long service lifespan and are significant for pulsed power system, smart power grid, and power electronics. Polypropylene (PP) is one of the most widely used dielectric materials for dielectric energy storage capacitors. It is of interest to investigate how to improve its electrical breakdown strength by nanodoping and the influencing mechanism of nanodoping on the electrical breakdown properties of polymer nanocomposites. PP/Al2O3 nanocomposite dielectric materials with various weight fraction of nanoparticles are fabricated by melt-blending and hot-pressing methods. Thermally stimulated current, surface potential decay, and dc electrical breakdown experiments show that deep trap properties and associated molecular chain motion are changed by incorporating nanofillers into polymer matrix, resulting in the variations in conductivity and dc electrical breakdown field of nanocomposite dielectrics. Then, a charge transport and molecular displacement modulated electrical breakdown model is utilized to simulate the dc electrical breakdown behavior. It is found that isolated interfacial regions formed in nanocomposite dielectrics at relatively low loadings reduce the effective carrier mobility and strengthen the interaction between molecular chains, hindering the transport of charges and the displacement of molecular chains with occupied deep traps. Accordingly, the electrical breakdown strength is enhanced at relatively low loadings. Interfacial regions may overlap in nanocomposite dielectrics at relatively high loadings so that the effective carrier mobility decreases and the interaction between molecular chains may be weakened. Consequently, the molecular motion is accelerated by electric force, leading to the decrease in electrical breakdown strength. The experiments and simulations reveals that the influence of nanodoping on dc electrical breakdown properties may origin from the changes in the charge transport and molecular displacement characteristics caused by interfacial regions in nanocomposite dielectrics.

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Solodukha, V. A., G. G. Chigir, V. A. Pilipenko, V. A. Filipenya, and V. A. Gorushko. "Reliability Express Control of the Gate Dielectric of Semiconductor Devices." Devices and Methods of Measurements 9, no. 4 (December 17, 2018): 308–13. http://dx.doi.org/10.21122/2220-9506-2018-9-4-308-313.

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The key element determining stability of the semiconductor devices is a gate dielectric. As its thickness reduces in the process of scaling the combined volume of factors determining its electrophysical properties increases. The purpose of this paper is development of the control express method of the error-free running time of the gate dielectric and study the influence of the rapid thermal treatment of the initial silicon wafers and gate dielectric on its reliability.The paper proposes a model for evaluation of the reliability indicators of the gate dielectrics as per the trial results of the test MDS-structures by means of applying of the ramp-increasing voltage on the gate up to the moment of the structure breakdown at various velocities of the voltage sweep with measurement of the IV-parameters. The proposed model makes it possible to realize the express method of the reliability evaluation of the thin dielectrics right in the production process of the integrated circuits.On the basis of this method study of the influence of the rapid thermal treatment of the initial silicon wafers of the KEF 4.5, KDB 12 wafers and formed on them by means of the pyrogenic oxidation of the gate dielectric for the error-free running time were performed. It is shown, that rapid thermal treatment of the initial silicon wafers with their subsequent oxidation results in increase of the error-free running time of the gate dielectric on average from 12.9 to 15.9 years (1.23 times greater). Thermal treatment of the initial silicon wafers and gate dielectric makes it possible to expand the error-free running time up to 25.2 years, i.e.1.89 times more, than in the standard process of the pyrogenic oxidation and 1.5 times more, than under application of the rapid thermal treatment of the initial silicon wafers only.

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Virchenko, Yu P. "One-dimensional stochastic model of radiative heat transfer in dielectric medium." Functional materials 23, no. 1 (March 15, 2016): 75–82. http://dx.doi.org/10.15407/fm23.01.075.

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You, Seung-Won, Dong Hwi Lee, Manh Cuong Nguyen, Yoon Seok Jeon, Duc-Tai Tong, Hyun Joon Bang, Jae Kyoung Jeong, and Rino Choi. "Effects of La Incorporation in Hf Based Dielectric on Leakage Conduction and Carrier Scattering Mechanisms." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 7590–92. http://dx.doi.org/10.1166/jnn.2015.11165.

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Metal-oxide-semiconductor field effect transistors (MOSFETs) with various doses of La-incorporated in Hafnium-based dielectrics were characterized to evaluate the effect of La on dielectric and device properties. It is found that the Poole-Frenkel emission model could explain our experimental leakage current conduction mechanism reasonably and barrier heights of localized Poole-Frenkel trap sites increase gradually with increasing La incorporation. Cryogenic measurement (from 100 K to 300 K) of MOSFETs reveals that, as the content of La incorporation in the dielectric increases, the more increase of maximum effective mobility has been found at low temperature. It is mainly attributed to the more reduction of phonon scattering due to higher content of La atoms at the interface of dielectric and channel. Though it is relatively small, the existence of La in dielectric reduces coulomb scattering rate as well.

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31

Heilmann, Rebecca, Aaro I. Väkeväinen, Jani-Petri Martikainen, and Päivi Törmä. "Strong coupling between organic dye molecules and lattice modes of a dielectric nanoparticle array." Nanophotonics 9, no. 2 (February 25, 2020): 267–76. http://dx.doi.org/10.1515/nanoph-2019-0371.

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AbstractPlasmonic structures interacting with light provide electromagnetic resonances that result in a high degree of local field confinement, enabling the enhancement of light-matter interaction. Plasmonic structures typically consist of metals, which, however, suffer from very high ohmic losses and heating. High-index dielectrics, meanwhile, can serve as an alternative material due to their low-dissipative nature and strong scattering abilities. We studied the optical properties of a system composed of all-dielectric nanoparticle arrays covered with a film of organic dye molecules (IR-792) and compared these dielectric arrays with metallic nanoparticle arrays. We tuned the light-matter interaction by changing the concentration in the dye film and reported the system to be in the strong coupling regime. We observed a Rabi splitting between the surface lattice resonances of the nanoparticle arrays and the absorption line of the dye molecules of up to 253 and 293 meV, for the dielectric and metallic nanoparticles, respectively. The Rabi splitting depends linearly on the square root of the dye molecule concentration, and we further assessed how the Rabi splitting depends on the film thickness for a low dye molecule concentration. For thinner films of thicknesses up to 260 nm, we observed no visible Rabi splitting. However, a Rabi splitting evolved at thicknesses from 540 to 990 nm. We performed finite-difference time-domain simulations to analyze the near-field enhancements for the dielectric and metallic nanoparticle arrays. The electric fields were enhanced by a factor of 1200 and 400, close to the particles for gold and amorphous silicon, respectively, and the modes extended over half a micron around the particles for both materials.

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Abdullah, Estabraq T. "Effects of Thicknesses of Two Different Gate Insulators on the Performance of Pentacene Based Organic Field Effect Transistor." BASRA JOURNAL OF SCIENCE 39, no. 1 (January 1, 2021): 56–66. http://dx.doi.org/10.29072/basjs.202114.

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In this paper, a simulation of the electrical performance for Pentacene-based top-contact bottom-gate (TCBG) Organic Field-Effect Transistors (OFET) model with Polymethyl methacrylate (PMMA) and silicon nitride (Si3N4) as gate dielectrics was studied. The effects of gate dielectrics thickness on the device performance were investigated. The thickness of the two gate dielectric materials was in the range of 100-200nm to maintain a large current density and stable performance. MATLAB simulation demonstrated for model simulation results in terms of output and transfer characteristics for drain current and the transconductance. The layer thickness of 200nm may result in gate leakage current points to the requirement of optimizing the thickness of different layers for better performance.

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Xia, Rong. "Characteristic Analysis and Measurement of Dielectric Loss in Non-Linear Insulating Materials." Advanced Materials Research 986-987 (July 2014): 1471–76. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.1471.

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Non-linear insulating material is widely used in the insulations of XLPE cable terminations and stator windings insulation of electric machines, and has obvious capability to improve the distribution of electric field. Actually, the dielectric loss factor of non-linear insulating materials is not equal to the tanδ describing linear insulating materials, and depends on applied voltage and their structures. This paper firstly discusses the difference between ac loss characteristic of non-linear dielectrics and linear dielectrics and presents a kind model of non-linear composite material. Based on the model, specific characterization and measurement methods and their numeric simulation analysis are given. Finally, a measuring system for non-linear insulating materials based on digital measuring technology is presented.

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Hau-Riege, Stefan P., and Carl V. Thompson. "The Effects of the Mechanical Properties of the Confinement Material on Electromigration in Metallic Interconnects." Journal of Materials Research 15, no. 8 (August 2000): 1797–802. http://dx.doi.org/10.1557/jmr.2000.0259.

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New low-dielectric-constant interlevel dielectrics are being investigated as alternatives to SiO2 for future integrated circuits. In general, these materials have very different mechanical properties from SiO2. In the standard model, electromigration-induced stress evolution caused by changes in the number of available lattice sites in interconnects is described by an effective elastic modulus, B. Finite element calculations were carried out to obtain B as a function of differences in the modulus, E, of interlevel dielectrics, for several stress-free homogeneous dilational strain configurations, for several line aspect ratios, and for different metallization schemes. In contradiction to earlier models, we found that for Cu-based metallization schemes with liners, a decrease in E by nearly two orders of magnitude has a relatively small effect on B, changing it by less than a factor of 2. However, B, and therefore the reliability of Cu interconnects, can be strongly dependent on the modulus and thickness of the liner material.

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35

Wiesmann, H. J., and H. R. Zeller. "A fractal model of dielectric breakdown and prebreakdown in solid dielectrics." Journal of Applied Physics 60, no. 5 (September 1986): 1770–73. http://dx.doi.org/10.1063/1.337219.

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36

McPherson, J. W., R. B. Khamankar, and A. Shanware. "Complementary model for intrinsic time-dependent dielectric breakdown in SiO2 dielectrics." Journal of Applied Physics 88, no. 9 (November 2000): 5351–59. http://dx.doi.org/10.1063/1.1318369.

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37

Di Lillo, Luigi, Andrea Bergamini, Dario Albino Carnelli, and Paolo Ermanni. "Frequency-dependent dielectric response model for polyimide-poly(vinilydenefluoride) multilayered dielectrics." Applied Physics Letters 101, no. 1 (July 2, 2012): 012906. http://dx.doi.org/10.1063/1.4731763.

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38

Walker, Jean Paul, Venkataraman Swaminathan, Aisha S. Haynes, and Haim Grebel. "Periodic Metallo-Dielectric Structures: Electromagnetic Absorption and its Related Developed Temperatures." Materials 12, no. 13 (June 30, 2019): 2108. http://dx.doi.org/10.3390/ma12132108.

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Multi-layer, metallo-dielectric structures (screens) have long been employed as electromagnetic band filters, either in transmission or in reflection modes. Here we study the radiation energy not transmitted or reflected by these structures (trapped radiation, which is denoted—absorption). The trapped radiation leads to hot surfaces. In these bi-layer screens, the top (front) screen is made of metallic hole-array and the bottom (back) screen is made of metallic disk-array. The gap between them is filled with an array of dielectric spheres. The spheres are embedded in a dielectric host material, which is made of either a heat-insulating (air, polyimide) or heat-conducting (MgO) layer. Electromagnetic intensity trapping of 97% is obtained when a 0.15 micron gap is filled with MgO and Si spheres, which are treated as pure dielectrics (namely, with no added absorption loss). Envisioned applications are anti-fogging surfaces, electromagnetic shields, and energy harvesting structures.

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39

Rau, E. I., and A. A. Tatarintsev. "Modification of the model of charging dielectrics under electron beam irradiation." Journal of Applied Physics 132, no. 18 (November 14, 2022): 184102. http://dx.doi.org/10.1063/5.0104628.

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In this paper, a number of drawbacks and contradictions of the existing models of charging dielectric targets under irradiation with defocused electron beams of moderate energies (0.2–20 keV) are briefly noted. In order to streamline and coordinate all experimental results and theoretical information concerning the phenomenon of charging under electron irradiation, it was necessary to reconsider some postulates of the standard model based on a simple dependence of the electron emission coefficient σ on irradiating electron energy E0. It is shown that the decisive role in establishing the equilibrium state of charging dielectrics is played by not only establishing the equilibrium value σ = 1, but also by reaching a certain critical value of the field Fin in the near-surface area of the target. This field is due to the generation of the two-layer bipolar distribution of charges. It enhances the electron emission owing to increasing the depth at which secondary electrons emerge and also owing to the previously neglected contribution of primary thermalized electrons. As a result, there occurs a fundamental transformation of the dependence of the total electron emission coefficient σc for a charged dielectric on the energy of primary electrons as compared to the case of an uncharged dielectric. Consequently, the value of the equilibrium energy E2C, at which σ = 1, is changed. It is established that times of reaching equilibrium states for electron emission δ( t) and for surface potentials Vs( t) may differ by orders of magnitude. Also, the charging kinetics is significantly affected by the process of radiation-induced formation of defects in the irradiated dielectric, which results in two charging time constants—fast and long-term ones.

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Yurtsever, Aycan, Martin Couillard, Jerome K. Hyun, and David A. Muller. "Thickness Measurements Using Photonic Modes in Monochromated Electron Energy-Loss Spectroscopy." Microscopy and Microanalysis 20, no. 3 (March 10, 2014): 723–30. http://dx.doi.org/10.1017/s1431927614000245.

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AbstractCharacteristic energies of photonic modes are a sensitive function of a nanostructures’ geometrical parameters. In the case of translationally invariant planar waveguides, the eigen-energies reside in the infrared to ultraviolet parts of the optical spectrum and they sensitively depend on the thickness of the waveguide. Using swift electrons and the inherent Cherenkov radiation in dielectrics, the energies of such photonic states can be effectively probed via monochromated electron energy-loss spectroscopy (EELS). Here, by exploiting the strong photonic signals in EELS with 200 keV electrons, we correlate the energies of waveguide peaks in the 0.5–3.5 eV range with planar thicknesses of the samples. This procedure enables us to measure the thicknesses of cross-sectional transmission electron microscopy samples over a 1–500 nm range and with best-case accuracies below ±2%. The measurements are absolute with the only requirement being the optical dielectric function of the material. Furthermore, we provide empirical formulation for rapid and direct thickness estimations for a 50–500 nm range. We demonstrate the methodology for two semiconducting materials, silicon and gallium arsenide, and discuss how it can be applied to other dielectrics that produce strong optical fingerprints in EELS. The asymptotic form of the loss function for two-dimensional materials is also discussed.

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Wang, Zhi-Hang, Jin-Yu Xu, Er-Lei Bai, and Liang-Xue Nie. "Dielectric Model of Carbon Nanofiber Reinforced Concrete." Materials 13, no. 21 (October 30, 2020): 4869. http://dx.doi.org/10.3390/ma13214869.

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The formula describing the relationship between the dielectric constant of a composite and the dielectric constants or volume rates of its components is called a dielectric model. The establishment of a cement concrete dielectric model is the basic and key technique for applying electromagnetic wave technology to concrete structure quality testing and internal damage detection. To construct the dielectric model of carbon nanofiber reinforced concrete, the carbon nanofiber reinforced concrete was measured by the transmission and reflection method for dielectric constant ε, and ε,, in the frequency range of 1.7~2.6 GHz as the fiber content was 0, 0.1%, 0.2%, 0.3% and 0.5%. Meanwhile, concrete was considered as a composite material composed of three phases, matrix (mortar), coarse aggregate (limestone gravel) and air, and the dielectric constants and volume rates of each component phase were tested. The Brown model, CRIM (Complex Refractive Index Model) model and Looyenga model commonly used in composite materials were modified based on the experimental data, suitable dielectric models of carbon nanofiber reinforced concrete were constructed, and a reliability check and error analysis of the modified models were carried out. The results showed that the goodness of fit between the calculated curves based on the three modified models and the measured curves was very high, the accuracy and applicability were very strong and the variation rule for the dielectric constant of carbon nanofiber concrete with the frequency of electromagnetic wave could be described accurately. For ε, and ε,,, the error between the dielectric constant calculated by the three modified models and the corresponding measured values was very small. For the dielectric constant ε,, the average error was maintained below 1.2%, and the minimum error was only 0.35%; for the dielectric constant ε,,, the average error was maintained below 3.55%.

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42

Holm, Sverre. "Time domain characterization of the Cole-Cole dielectric model." Journal of Electrical Bioimpedance 11, no. 1 (January 1, 2020): 101–5. http://dx.doi.org/10.2478/joeb-2020-0015.

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Abstract The Cole-Cole model for a dielectric is a generalization of the Debye relaxation model. The most familiar form is in the frequency domain and this manifests itself in a frequency dependent impedance. Dielectrics may also be characterized in the time domain by means of the current and charge responses to a voltage step, called response and relaxation functions respectively. For the Debye model they are both exponentials while in the Cole-Cole model they are expressed by a generalization of the exponential, the Mittag-Leffler function. Its asymptotes are just as interesting and correspond to the Curie-von Schweidler current response which is known from real-life capacitors and the Kohlrausch stretched exponential charge response.

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43

Holm, Sverre. "Time domain characterization of the Cole-Cole dielectric model." Journal of Electrical Bioimpedance 11, no. 1 (December 31, 2020): 101–5. http://dx.doi.org/10.2478/joeb-2020-0015.

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AbstractThe Cole-Cole model for a dielectric is a generalization of the Debye relaxation model. The most familiar form is in the frequency domain and this manifests itself in a frequency dependent impedance. Dielectrics may also be characterized in the time domain by means of the current and charge responses to a voltage step, called response and relaxation functions respectively. For the Debye model they are both exponentials while in the Cole-Cole model they are expressed by a generalization of the exponential, the Mittag-Leffler function. Its asymptotes are just as interesting and correspond to the Curie-von Schweidler current response which is known from real-life capacitors and the Kohlrausch stretched exponential charge response.

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Barron, John, Alec Pickett, James Glaser, and Suchismita Guha. "Solution-Processed Organic and ZnO Field-Effect Transistors in Complementary Circuits." Electronic Materials 2, no. 2 (March 30, 2021): 60–71. http://dx.doi.org/10.3390/electronicmat2020006.

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The use of high κ dielectrics lowers the operating voltage in organic field-effect transistors (FETs). Polymer ferroelectrics open the path not just for high κ values but allow processing of the dielectric films via electrical poling. Poled ferroelectric dielectrics in p-type organic FETs was seen to improve carrier mobility and reduce leakage current when compared to unpoled devices using the same dielectric. For n-type FETs, solution-processed ZnO films provide a viable low-cost option. UV–ozone-treated ZnO films was seen to improve the FET performance due to the filling of oxygen vacancies. P-type FETs were fabricated using the ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) as the dielectric along with a donor–acceptor polymer based on diketopyrrolopyrrole (DPP-DTT) as the semiconductor layer. The DPP-DTT FETs yield carrier mobilities upwards of 0.4 cm2/Vs and high on/off ratios when the PVDF-TrFE layer is electrically poled. For n-type FETs, UV–ozone-treated sol–gel ZnO films on SiO2 yield carrier mobilities of 10−2 cm2/Vs. DPP-DTT-based p- and ZnO-based n-type FETs were used in a complementary voltage inverter circuit, showing promising characteristic gain. A basic inverter model was used to simulate the inverter characteristics, using parameters from the individual FET characteristics.

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Ayryan, Edik, Dmitry Divakov, Alexandre Egorov, Konstantin Lovetskiy, and Leonid Sevastianov. "Modelling Leaky Waves in Planar Dielectric Waveguides." EPJ Web of Conferences 226 (2020): 02003. http://dx.doi.org/10.1051/epjconf/202022602003.

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Experimentally observed leaky modes of a dielectric waveguide are characterised by a weak tunnelling of the light through the waveguide and its long-time propagation along the waveguide. Traditional mathematical models of leaky waveguide modes meet some contradictions resolved using additional considerations. We propose a model of leaky modes in a waveguide free from the above contradictions, akin to the quantum mechanical model of the “pseudo-stable” Gamow-Siegert states. By separating variables, from the complete problem for plane inhomogeneous waves we obtain a non-self-adjoint Sturm-Liouville problem to determine the complex coefficient of the phase delay of the studied mode. The solution of the complete wave problem determines the propagation cone for the leaky mode of the waveguide, inside which there are no contradictions. Thus, solution is in qualitative agreement with experimental data.

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46

Mohd Ghazali, Farah Afiqa, Wong Yi Jie, Mariatul Rawdhah Ahmad Fuaad, and Mohamed Sultan Mohamed Ali. "Soft dielectric elastomer microactuator for robot locomotion." Bulletin of Electrical Engineering and Informatics 9, no. 6 (December 1, 2020): 2286–93. http://dx.doi.org/10.11591/eei.v9i6.2208.

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This paper presents dielectric elastomer actuated robot locomotion and the development of a robotic model structure based using a dielectric elastomer actuator. A pre-stretched dielectric elastomer actuator is fabricated onto acrylic frames to form single and multiple robotic crawler models. The crawler models demonstrate forwards motion upon application of high voltage to the attached dielectric elastomer actuator. Characterizations revealed that the fabricated multiple crawler models showed results over the single crawler model in terms of locomotion potential. The maximum forward locomotion speed of the multiple crawler models is recorded as 1.2 mm/s. Nonetheless, precise results are highly attainable provided a structured and coherent fabrication technique of the dielectric elastomer actuator is implemented.

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Karelin, V. A., and Vl V. Salomatov. "A review of modern numerical and analytical models of heat transfer in a dielectric layer during melting due to microwave radiation." Journal of Physics: Conference Series 2119, no. 1 (December 1, 2021): 012074. http://dx.doi.org/10.1088/1742-6596/2119/1/012074.

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Abstract In this work, numerical and analytical solutions of heat transfer in a dielectric layer during melting in the microwave field were considered. We considered solutions, where the source term was obtained based on the solution of Maxwell equation, as well as using the Lambert law. The conditions applicable for analytical solutions, allowing the parametric analysis, are determined. The areas of application of the technology of microwave melting of dielectrics, in particular with melting ice on water, defrosting products, etc., were also considered.

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Bennett, Daniel, Maitane Muñoz Basagoiti, and Emilio Artacho. "Electrostatics and domains in ferroelectric superlattices." Royal Society Open Science 7, no. 11 (November 2020): 201270. http://dx.doi.org/10.1098/rsos.201270.

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The electrostatics arising in ferroelectric/dielectric two-dimensional heterostructures and superlattices is revisited within a Kittel model in order to define and complete a clear paradigmatic reference for domain formation. The screening of the depolarizing field in isolated ferroelectric or polar thin films via the formation of 180° domains is well understood, where the width of the domains w grows as the square-root of the film thickness d , following Kittel’s Law for thick enough films ( w ≪ d ). For thinner films, a minimum is reached for w before diverging to a monodomain. Although this behaviour is known to be qualitatively unaltered when the dielectric environment of the film is modified, we consider the quantitative changes in that behaviour induced on the ferroelectric film by different dielectric settings: as deposited on a dielectric substrate, sandwiched between dielectrics, and in a superlattice of alternating ferroelectric/dielectric films. The model assumes infinitely thin domain walls, and therefore is not expected to be reliable for film thickness in the nanometre scale. The polarization field P(r) does vary in space, deviating from ± P S , following the depolarizing field in linear response, but the model does not include a polarization-gradient term as would appear in a Ginzburg–Landau free energy. The model is, however, worth characterizing, both as paradigmatic reference, and as applicable to not-so-thin films. The correct renormalization of parameters is obtained for the thick-film square-root behaviour in the mentioned settings, and the sub-Kittel regime is fully characterized. New results are presented alongside well-known ones for a comprehensive description. Among the former, a natural separation between strong and weak ferroelectric coupling in superlattices is found, which depends exclusively on the dielectric anisotropy of the ferroelectric layer.

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Coak, Matthew J., Charles R. S. Haines, Cheng Liu, Stephen E. Rowley, Gilbert G. Lonzarich, and Siddharth S. Saxena. "Quantum critical phenomena in a compressible displacive ferroelectric." Proceedings of the National Academy of Sciences 117, no. 23 (May 26, 2020): 12707–12. http://dx.doi.org/10.1073/pnas.1922151117.

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The dielectric and magnetic polarizations of quantum paraelectrics and paramagnetic materials have in many cases been found to initially increase with increasing thermal disorder and hence, exhibit peaks as a function of temperature. A quantitative description of these examples of “order-by-disorder” phenomena has remained elusive in nearly ferromagnetic metals and in dielectrics on the border of displacive ferroelectric transitions. Here, we present an experimental study of the evolution of the dielectric susceptibility peak as a function of pressure in the nearly ferroelectric material, strontium titanate, which reveals that the peak position collapses toward absolute zero as the ferroelectric quantum critical point is approached. We show that this behavior can be described in detail without the use of adjustable parameters in terms of the Larkin–Khmelnitskii–Shneerson–Rechester (LKSR) theory, first introduced nearly 50 y ago, of the hybridization of polar and acoustic modes in quantum paraelectrics, in contrast to alternative models that have been proposed. Our study allows us to construct a detailed temperature–pressure phase diagram of a material on the border of a ferroelectric quantum critical point comprising ferroelectric, quantum critical paraelectric, and hybridized polar-acoustic regimes. Furthermore, at the lowest temperatures, below the susceptibility maximum, we observe a regime characterized by a linear temperature dependence of the inverse susceptibility that differs sharply from the quartic temperature dependence predicted by the LKSR theory. We find that this non-LKSR low-temperature regime cannot be accounted for in terms of any detailed model reported in the literature, and its interpretation poses an empirical and conceptual challenge.

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Katunin, Andrzej, and Katarzyna Krukiewicz. "Electrical percolation in composites of conducting polymers and dielectrics." Journal of Polymer Engineering 35, no. 8 (October 1, 2015): 731–41. http://dx.doi.org/10.1515/polyeng-2014-0206.

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Abstract This article deals with the electrical conductivity of a composite of two polymers, one of which is a conducting polymer, whereas the second is a dielectric. The problem was formulated within the framework of electrical percolation, i.e., the percolation thresholds, which allow for a high electrical conductivity, is under investigation. For this purpose, a numerical model was developed, and its parameters were analyzed and discussed. Based on the determined thresholds, it was possible to evaluate the weight ratios of the conducting-dielectric polymers in a composite. The proposed approach allows for reducing the manufacturing cost of composite material with respect to conducting polymers with simultaneous retaining of high conductance properties of conducting polymers, as well as durability and flexibility of dielectrics.

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Journal articles on the topic 'Dielectic modes'

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