Dielectric loss

About: Dielectric loss is a research topic. Over the lifetime, 20296 publications have been published within this topic receiving 349254 citations.

Recent advances in high-k nanocomposite materials for embedded capacitor applications

Abstract: In this paper, a wide variety of high dielectric constant (k) composite materials which have been developed and evaluated for embedded capacitor application are reviewed. Current research efforts toward achieving high dielectric performance including high-k and low dielectric loss for polymer composites are presented. New insights into the effect of unique properties of the nanoparticle filler, filler modification and the dispersion between filler and polymer matrix on the dielectric properties of the nanocomposites are discussed in details.

Microscopic Calculation of Dielectric Loss at Microwave Frequencies for Complex Perovskite Ba(Zn1/3Ta2/3)O3

Abstract: The dielectric loss tangent at microwave frequencies for the complex perovskite Ba(Zn1/3Ta2/3)O3 was calculated with respect to the degree of structural disorder on B sites. Starting out from the equations of ion motion, dielectric loss was expressed in terms of the pair-correlation functions corresponding to the ordering of Zn and Ta ions on B sites. The characteristic length included in the pair-correlation functions corresponds to the average size of the region containing disorder in ion arrangements on B sites; thus the relation between the structural disorder on the B site and the dielectric loss tangent at microwave frequencies was clarified theoretically. The numerical results show that the microwave loss tangent values change their power from – 3 to – 6 with increasing degree of order on the B site, which agrees well with the experimental observations. Results obtained here confirm the physical origin of the microwave loss of complex perovskite Ba(Zn1/3Ta2/3)O3.

Impacts of the Real and Imaginary Components of Relative Permittivity on Time Domain Reflectometry Measurements in Soils

Abstract: Time domain reflectometry (TDR) is widely used for routine field monitoring of water content and salts in soils. Most estimates of water content assume the TDR-measured apparent relative permittivity, e a , is a good approximation for the real component, e τ ', of the soil's complex relative permittivity with the magnitude of e τ ' being determined primarily by water content. We examine this assumption and show that e a is influenced by both the real and imaginary components of the relative permittivity. Increases in e a resulted from the de conductivity and dielectric loss arising from the presence of ions in solution and clay content. At water contents above 0.15 m 3 m -3 in soils with high clay content and/or salt, specific calibrations are needed for precise determinations of water content from TDR. We use the wave propagation equations to separate the real and imaginary component contributions to e a . The Giese and Tiemann interpretation for de conductivity was again shown to he within 10% of that from a conductance meter and this fact was used to propose a method using only TDR data to separate real and imaginary components of the relative permittivity. It was found that the dielectric losses and conductive losses did not differ according to the source of conductivity, whether from clay content in the soil matrix or electrolyte in the soil solution.