Dielectric behavior and phase transition in perovskite oxide Pb(Fe[sub ½]Nb[sub ½])[sub 1−x]Ti[sub x]O₃ single crystal

Abstract

Perovskite oxide Pb(Fe[sub ½]Nb[sub ½])₀.₅₂Ti₀.₄₈O₃ crystals, which were grown using a modified Bridgman method, show a high low-frequency dielectric constant response at room temperature. The Curie phase transition occurs at 523 K. The characteristic frequency of the dielectric dispersion versus the inverse of temperature obeys an Arrhenius relation, which shows a thermally activated behavior. The thermal activation energy for relaxation was found to be ~0.14 eV. The high dielectric permittivity was attributed to oxygen vacancies and conduction via hopping carriers.