Nucleation of the ferroelectric phase in the (Pb xSr 1− x)TiO 3 system

Abstract

The diffuseness of the ferroelectric phase transition depends on the size of the ferroelectric nuclei and therefore, by using a power law model, the size of the ferroelectric nuclei was determined to be between 40 and 60 Å. Diffuse phase transitions were observed in the (Pb x Sr 1− x )TiO 3 system upon transforming from the cubic paraelectric phase to the tetragonal ferroelectric phase. The diffuseness of the phase transition was quantified by measuring the dielectric constant as a function of temperature. Using these curves of dielectric constant vs temperature a semi-empirical method was used to determine the diffuseness coefficient, δ.