Microwave dielectric relaxation of ferroelectric PLZT ceramics in the range of 300-900 K

Abstract

Dielectric response of PLZT(x/65/35) ceramics (with x = 0, 2, 4, 5) was studied using radio frequency and microwave techniques in the temperature range 300−900 K and with a frequency range of 102 Hz-3 × 109 Hz. Dielectric relaxation appears around 1 × 109 Hz at room temperature. The relaxation frequency softens at Tc and the dielectric relaxation exists in both paraelectric and ferroelectric phases and depends on x the lanthanum concentration. A model of correlation chains gives some keys for understanding the frequency behaviour of such materials.