Yttrium barium copper oxide‐filled polystyrene as a dielectric material

Abstract

Electrical impedance measurements are carried out on high temperature superconducting ceramic Yttrium Barium Copper Oxide (YBCO)-Polystyrene (PS) composite materials, in which superconducting particles are embedded in polystyrene matrix. The results of impedance versus frequency (100 Hz-13 MHz), phase angle versus temperature for volume percentage of superconductor (0-40%) are presented. No marked transition in phase angle is observed when the material goes through the superconducting transition temperature of the filler. The dielectric constant and losses increase with increasing YBCO content. However the increase in losses is modest and the excellent dielectric properties of the composites are not adversely affected. The system conforms to Clausius-Mossotti equation. Dipole moment of YBCO particles and polarizability of the composites are calculated using the Clausius-Mossotti approaches.

Manufacture of electrical and magnetic graded and anisotropic materials for novel manipulations of microwaves

“…The data at 77 K was obtained by submerging the waveguide measurement jig in liquid nitrogen. In accordance with previous studies [ 20 , 21 ], the quantity could be controlled by both the YBCO fraction and temperature, as shown in figure 1 c , where n is related to the refractive index, but ignoring the imaginary components ε ′′ and μ ′′, which tend to be relatively lossy in these composites; for example, the acrylonitrile butadiene styrene (ABS)—YBCO composite had a loss tangent at 15 GHz of 0.025 at 0.2 vol% YBCO. The increase in n with YBCO filler fraction derived from the increase of ε ′ with filler fraction shown in figure 1 a , in accordance with the effective medium theory of Bruggeman [ 5 ], which provided a good fit to the effective permittivity data for YBCO volume fractions up to 50% using ε ′=55 for the filler particles (note, considerably smaller than the bulk permittivity of BaTiO 3 of at least several hundreds).…”

Low dielectric loss and weak frequency dependence of dielectric permittivity of the CeO2/polystyrene nanocomposite films

“…13 Dielectric response of PS composites has been reported by some groups. [14][15][16][17] But to the best of our knowledge, the CeO 2 / PS composite has never been reported for the dielectric properties.…”