A Way to Design Diaelectric Materials

TL;DR

This paper introduces a new molecular field theory for ferroelectrics that predicts conditions under which diaelectric states can be achieved, aiding the design of novel diaelectric materials with specific dielectric properties.

Contribution

It develops a comprehensive molecular field theory including SDIMF and WMF, providing a new approach to design diaelectric materials and predict dielectric behavior in ferroelectrics.

Findings

Diaelectric state occurs when SDIMF opposes WMF with sufficient strength.

Large static dielectric constant can be achieved when SDIMF and WMF oppose each other with small SDIMF.

The theory offers a new pathway for designing materials with tailored dielectric properties.

Abstract

Considering the coupling between electric polarization and crystal lattice in ferroelectrics, the authors propose a new molecular field theory. It not only includes the classical Weiss Molecular field (WMF), but also the spontaneous distortion inducted molecular field (SDIMF). This theory tells us that diaelectric state will appear in ferroelectrics when the direction of SDIMF is opposite to WMF and its strength is strong enough. In other words, we found a way to design diaelectric materials (diaelectrics). Besides, the theory also predicts the appearance of large static dielectric constant state in ferroelectric phase, when the SDIMF and WMF are in opposite direction but the SDIMF strength is relative small. This is definitely valuable in mentoring the design of new relevant materials.