Depolarization of ferroelectric materials measured by their piezoelectric and elastic response.

Depolarization in ferroelectric materials limits their piezoelectric applications and needs careful calibration for device constructions. With BaTiO 3 and PbSc 0.5 Ta 0.5 O 3 as prototypic ferroelectrics we demonstrate how to apply Resonant Piezoelectric Spectroscopy, RPS, to measure the direct and the converse piezoelectric effects as a function of temperature to detect depolarization via the collapse of the piezoelectric effect and the anomaly of elastic moduli. Comparison of the RPS data with in-situ d 33 measurements on a BaTiO 3 ceramic shows that the temperature evolution of the longitudinal piezoelectric coefficient d 33 can be determined with high accuracy. This makes RPS a complementary and convenient method for the investigation of polar phase transitions and the thermal evolution of the piezoelectric effect. Finally, the observation of an elastic anomaly concomitant to depolarization indicates that elastic measurements are an indirect means to measure the depolarization temperature in ferroelectrics. • RPS is a versatile and complementary technique for measuring depolarization in ferroelectrics with the ability for in-situ poling. • RPS can accurately measure the thermal evolution of the longitudinal piezoelectric coefficient d 33 , which is important for many technological applications. • Elastic measurements are an indirect means to measure the depolarization temperature in ferroelectrics. [ABSTRACT FROM AUTHOR]