Theory of Dielectric Absorption Line Shape in Dielectrics and Ferroelectrics

TL;DR

This paper develops a theoretical framework for dielectric spectra, analyzing line shapes influenced by broadening mechanisms, and highlights how studying these can reveal information about disorder in materials like relaxor ferroelectrics.

Contribution

The paper introduces a comprehensive theory of dielectric line shapes considering both homogeneous and inhomogeneous broadening effects in dielectrics and ferroelectrics.

Findings

Calculated dielectric absorption line shapes for various broadening mechanisms.

Discussed conditions under which hole burning can be observed.

Showed that line shape analysis reveals disorder-related properties in materials.

Abstract

We present the theory of dielectric spectra allowing for homogeneous and inhomogeneous broadening mechanisms contributions. The dielectric absorption line shape for oscillators with memory and Debye type relaxors with distribution of, respectively, resonant frequencies and relaxation times (due to random electric fields distribution) has been calculated. The conditions of hole burning observation are discussed. It is shown that the investigations of the inhomogeneously broadened line shape and width as well as hole burning can give valuable information about the distribution of random fields and relaxation times. The latter seems to be extremely important for the disordered systems like supercooled liquids and relaxor ferroelectrics.