The polarizability model for ferroelectricity in perovskite oxides

TL;DR

This paper reviews the polarizability model's application to ferroelectric perovskite oxides, emphasizing nonlinear effects, lattice dynamics, and comparisons with experimental data to predict new phenomena.

Contribution

It introduces and discusses the polarizability model's nonlinear and lattice dynamical aspects, applying it to ferroelectric oxides and exploring relaxor ferroelectrics and phase transitions.

Findings

Model successfully explains experimental ferroelectric behaviors

Nonlinear solutions reveal complex phase transition phenomena

Predictions include novel ferroelectric effects

Abstract

This article reviews the polarizability model and its applications to ferroelectric perovskite oxides. The motivation for the introduction of the model is discussed and nonlinear oxygen ion polarizability effects and their lattice dynamical implementation outlined. While a large part of this work is dedicated to results obtained within the self-consistent-phonon approximation (SPA), also nonlinear solutions of the model are handled which are of interest to the physics of relaxor ferroelectrics, domain wall motions, incommensurate phase transitions. The main emphasis is to compare the results of the model with experimental data and to predict novel phenomena.