Diffuse ferroelectric transition and relaxational dipolar freezing in (Ba,Sr)TiO₃

Abstract

The effect of Sr2+ substitution on the structure and dielectric behaviour of BaTiO3 is reported. It is shown that the smearing of the variation of dielectric constant with temperature in such samples is not due to compositional inhomogeneities. Observation of relaxational dipolar freezing below the hump temperature indicates the similarity of diffuse ferroelectric transition and orientational glass behaviour.

Influence of diffuse phase transition on the anelastic behavior of Nb-doped Pb(Zr0.53Ti0.47)O3 ceramics

“…Debye-type relaxation is associated with the relaxation of dipole clusters or polar regions [48], which should freeze at T f , and consequently, the relaxation should not be observed at temperatures below T f or higher than T B .…”

Ferroelectric relaxor behavior in Ba0.925Dy0.075TiO3 ceramic

“…On partial substitution of dopants like Ca, Sr, Zr [10][11][12], the variation of ε around Tc gets broadened out in ceramics and single crystal samples both. Broadening increases with increasing concentration of the dopant, as also does the deviation from Curie-Weiss behavior at temperatures above the peak temperature (Tm) of the ε-T variation.…”

“…Different nano-regions in a macroscopic sample transform at different temperatures giving rise to a range of transformation temperatures, the so-called 'Curie range'. Thus the compositional fluctuation [6,11], in an otherwise compositionally homogenous system leads to diffuse phase transition (DPT). In compositionally homogenous systems quenched random disorder breaks the long range polar order at unit cell level, leading to broad ε-T response [7].…”

Role of the dielectric constant of ferroelectric ceramic in enhancing the ionic conductivity of a polymer electrolyte composite

“…The Sr 2+ modified BaTiO 3 ferroelectric ceramic, abbreviated as BST, was prepared using a novel semi-chemical route 12 . Fine powders of BST is obtained by crushing the sintered pellets in agate pistle-mortar and then sieving it by using a 400 mesh sieve.…”