Ferroelectric-dielectric tunable composites
- 1 April 2006
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 99 (7), 074104
- https://doi.org/10.1063/1.2186004
Abstract
The dielectric response of ferroelectric-dielectric composites is theoretically addressed. Dielectric permittivity, tunability (relative change of the permittivity driven by dc electric field), and loss tangent are evaluated for various composite models. The analytical results for small dielectric concentration and relative tunability are obtained in terms of the traditional electrostatic consideration. The results for large tunability are obtained numerically. A method is proposed for the evaluation of the tunability and loss at large concentrations of the dielectric. The basic idea of the method is to reformulate the effective medium approach in terms of electrical energies stored and dissipated in the composite. The important practical conclusion of the paper is that, for random ferroelectric-dielectric composite, the addition of small amounts of a linear dielectric into the tunable ferroelectric results in an increase of the tunability of the mixture. The loss tangent of such composites is shown to be virtually unaffected by the addition of moderate amounts of the low-loss dielectric. The experimental data for based composites are analyzed in terms of the theory developed and shown to be in a reasonable agreement with the theoretical results.
Keywords
This publication has 15 references indexed in Scilit:
- Three-dimensional polarization imaging of (Ba,Sr)TiO3:MgO compositesApplied Physics Letters, 2005
- Can the addition of a dielectric improve the figure of merit of a tunable material?Journal of the European Ceramic Society, 2003
- Silicon substrate integrated high Q-factor parallel-plate ferroelectric varactors for microwave/millimeterwave applicationsApplied Physics Letters, 2003
- Ferroelectric Materials for Microwave Tunable ApplicationsJournal of Electroceramics, 2003
- Breakthrough advances in low loss, tunable dielectric materialsMaterials Research Innovations, 1999
- Dielectric response of microcomposite ferroelectricsFerroelectrics, 1998
- Dielectric tunability of barium strontium titanate/silicone-rubber compositeJournal of Physics: Condensed Matter, 1998
- Effective dielectric response of nonlinear compositesPhysical Review B, 1993
- The role of the background dielectric susceptibility in uniaxial ferroelectricsFerroelectrics, 1986
- Berechnung verschiedener physikalischer Konstanten von heterogenen Substanzen. I. Dielektrizitätskonstanten und Leitfähigkeiten der Mischkörper aus isotropen SubstanzenAnnalen der Physik, 1935