Non-linear dielectric properties in based-PMN relaxor ferroelectrics

The investigation of the non-linear dielectric response in ferroelectric materials has become one of the most important issues in the field of ferroelectricity due to its technological and scientific interest. Rather, from the practical point of view the understanding of the non-linear dielectric properties is essential to improve the performance of ferroelectric multilayer capacitors and actuators devices, which commonly operate at high field levels. On the other hand, the non-linear (NL) dielectric response to large electric fields has been revealed as a powerful technique to investigate the physical origin of the dielectric relaxor state. In this work, low frequency dielectric measurements were performed in 0.9[Pb(Mg1/3Nb3/2)O3]-0.1PbTiO3 (PMN-PT) relaxor ceramics in a wide frequency and temperature range. The non-linear dielectric properties were investigated by using the measurements of the dielectric permittivity of the PMN-PT as a function of the dc “bias” driving field. The obtained results were analyzed within the framework of the current models for the dielectric response of relaxor ferroelectrics.