The Effect of Bias Field on Dielectric Response in Lead Ferrotantalate Ceramics

Studies of dielectric properties of PbFe1/2Ta1/2O3 ceramics at low- and infra-low-frequencies under bias field over a wide range of temperatures are reported. Applied bias field is found to broaden the ϵ′(Т) maxima shifting positions Тm of the maximums to higher temperatures. Additional anomalies in the dielectric response are revealed at T<Тm. The anomalies in the vicinity of Тm are related to structural change at phase transition, while those observed at TТm – to magneto-electric interactions in PbFe1/2Ta1/2O3.