Temperature dependent tunability data and modelling in the paraelectric Ba0.7Sr0.3TiO3 solid solutions

Abstract

The fi eld dependence of the dielectric constant (dc-tunability) as a function of temperature in (Ba,Sr)TiO3 ceramics was investigated. Dense and homogeneous BaxSr1-xTiO3 ceramics prepared by Pechini method show low losses, high dielectric constant of ~4000 and typical ferroelectric properties at room temperature. The dctunability at various temperatures, including the Curie range, was obtained. A single polarization mechanism was used in the polar state of the ceramics to describe the tunability data. A good correlation between theory and experiment was found. In the paraelectric phase, a model of random uncorrelated non-interacting dipolar units in a double well potential was considered.

Keywords

• Pechini method
• DC-tunability
• Nanopolar regions