Eur. Phys. J. B 9, 599-604 (1999)
https://doi.org/10.1007/s100510050803

A Raman and dielectric study of ferroelectric Ba(Ti_1-xZr_x)O₃ ceramics

¹ Laboratoire de Physique de la Matière Condensée, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens, France
² Institut de Chimie de la Matière Condensée de Bordeaux, CNRS, 87 avenue du Dr. A. Schweitzer, 33608 Pessac, France

Corresponding author: ^a robert.farhi@sc.u-picardie.fr

Received: 25 September 1998
Published online: 15 June 1999

Abstract

Dielectric and Raman scattering experiments were performed on various ceramics with composition Ba(Ti1-xZr_x)O₃. Such lead-free, environmental-friendly materials were shown, from dielectric measurements, to exhibit behaviours extending from conventional to relaxor ferroelectrics on increasing the zirconium concentration. The evolution of the Raman spectra was studied as a function of temperature for various compositions, and the spectroscopic signature of the corresponding phases was determined. In the relaxor state, the variation of the integrated intensity of the Raman lines with temperature showed a plateau at low temperature. This anomaly was also detected as a peak in depolarization current measurements, and attributed to ergodicity breaking which characterizes usual relaxor systems. Raman results hint at locally rhombohedral polar nanoregions resulting from the random fields associated with Zr ions.