Landau, Ginzburg, Devonshire and others

TL;DR

This paper critically examines the Landau-Ginzburg-Devonshire theory of ferroelectricity, highlighting its approximate nature and analyzing the contributions and limitations of its foundational authors.

Contribution

It offers a novel perspective by deriving the Landau theory from mechanical models and the Ising model, emphasizing its qualitative and approximate character.

Findings

Landau-Ginzburg-Devonshire theory is fundamentally approximate.

The paper derives the theory from mechanical and Ising models.

It critically discusses the contributions and limitations of the three authors.

Abstract

Macroscopic modelling of ferroelectric properties refers usually to Landau-Ginzburg-Devonshire theory. This paper questions the meaningfulness of this term, discussing contributions of the three authors to what is supposed to be a theory. The limitations of every contribution are analyzed. In the main text and, to more extent in the Supplementary Material, the Landau theory is presented from an unusual perspective starting from simple mechanical models of spontaneous symmetry breaking and finishing by the Ising model. The aim of the presentation is to emphasize along with the qualitative breakthroughs the approximate character of macroscopic modelling associated with the above three authors.