Polarization relaxation in thin-film relaxors compared to that in ferroelectrics

TL;DR

This study compares polarization relaxation behaviors in thin-film relaxors and ferroelectrics, revealing distinct mechanisms for dielectric nonlinearity and hysteresis linked to domain configurations and dipole dynamics.

Contribution

It provides new insights into the different polarization relaxation mechanisms in relaxor and ferroelectric thin films through comprehensive dielectric property analysis.

Findings

Ferroelectric domains influence dielectric nonlinearity and hysteresis.

Relaxor relaxations are driven by dipole interactions in a random field.

High-temperature hysteresis in (Ba,Sr)TiO3 exhibits relaxor-like behavior.

Abstract

Epitaxial thin films of relaxor PbMg1/3Nb2/3O3 and PbSc0.5Nb0.5O3, and ferroelectric PbZr0.65Ti0.35O3, Pb0.955La0.045Zr0.65Ti0.35O3, and Ba0.4Sr0.6TiO3 were prepared, and their dielectric properties were studied in a broad range of the measurement conditions. In the ferroelectric state, the presence and the change of configuration of the domains determined both the dynamic dielectric nonlinearity and the polarization hysteresis. In thin-film relaxors, the orientation of the randomly interacting dipoles in a random field was responsible for the dynamic dielectric nonlinearity, while the observed hysteresis was suggested to arise due to connection between the applied field and the relaxation times of both the dipoles and the internal field. In thin-film (Ba,Sr)TiO3, the high-temperature dielectric hysteresis was found to be relaxorlike.