High Frequency Dielectric Relaxation in Lanthanum Modified PbTiO

Dielectric measurements of lanthanum modified lead titanate ceramics were carried out in a frequency and temperature range of 70 × 10 Hz – 2 × 10 Hz and 300 K 420 K, respectively. Dielectric relaxation appears around 7 × 10 Hz at room temperature, and the maximum of the dielectric relaxation was around 393 K, the transition temperature (T c ). The relaxation frequency passes through a minimum at T c and the dielectric relaxation exists in both paraelectric and ferroelectric phases. A fitting of the experimental data with the Debye relations gives some keys for understanding the dielectric behavior of such materials.