Temperature-dependent ferroelectric domain alignment in PLZT ceramic

Abstract

The temperature dependence of the remnant dielectric polarization, P_R(T), effective birefringence parameter, $\overline{\mathrm{\Delta n}}\mathrm{(T)}$ , of hot‐pressed ferroelectric 8/65/35 lead zirconate‐lead titanate‐lanthanum oxide (PLZT) has been investigated. The material exhibits relaxor behavior and a diffuse phase transition in the neighborhood of 102 to 109 °C. The P_R(T) and $\overline{\mathrm{\Delta n}}\mathrm{(T)}$ , however, dramatically decrease at temperatures distinctly lower than the diffuse phase transition temperature region. A ferroelectric domain alignment in poled samples, and a thermally influenced disalignment is proposed in order to account for the additional observed behavior. A mechanism based upon grain‐boundary heterogeneities is suggested. Differential thermal analysis data are consistent with a domain disalignment scheme.