Dielectric, pyroelectric, and thermally stimulated depolarization current investigations on lead-lanthanum zirconate-titanate-x/95/5 ceramics with La content x=0.5%–4%

Abstract

It is shown that La dopants have a strong influence on the antiferroelectric‐ ferroelectric‐paraelectric (AFE‐FE‐PE) phase transitions and properties of the lead‐lanthanum zirconate‐titanate‐x/95/5 ceramics (with La contents x=0.5%–4%). The occurrence of the ferroelectric microdomains, dispersed in the AFE and PE matrices, gives rise to properties typical for ferroelectric relaxors. The space‐charge concentration polarization, formed by some mobile ion defects, plays an important role in this behavior. This space‐charge polarization and its interaction with the spontaneous polarization was investigated by dielectric, pyroelectric, and thermally stimulated depolarization current measurements. A qualitative model of interpretation is discussed.