Convert widespread paraelectric perovskite to ferroelectrics

TL;DR

This paper introduces a general thin-film design approach using first-principles calculations to convert widespread paraelectric CaTiO$_3$-type perovskites into ferroelectric BiFeO$_3$-type structures by manipulating boundary conditions.

Contribution

It proposes a novel method to stabilize ferroelectric BFO-type structures in CTO-type perovskites, expanding their potential applications.

Findings

Distinct dependence of antiferroelectricity and ferroelectricity on boundary conditions.

Oxygen octahedral rotations influence ferroelectric stabilization.

Method applicable to various CTO-type perovskite oxides.

Abstract

While nature provides a plethora of perovskite materials, only a few exhibits large ferroelectricity and possibly multiferroicity. The majority of perovskite materials have the non-polar CaTiO$_3$(CTO)structure, limiting the scope of their applications. Based on effective Hamiltonian model as well as first-principles calculations, we propose a general thin-film design method to stabilize the functional BiFeO$_3$(BFO)-type structure, which is a common metastable structure in widespread CaTiO$_3$-type perovskite oxides. It is found that the improper antiferroelectricity in CTO-type perovskite and ferroelectricity in BFO-type perovskite have distinct dependences on mechanical and electric boundary conditions, both of which involve oxygen octahedral rotation and tilt. The above difference can be used to stabilize the highly polar BFO-type structure in many CTO-type perovskite materials.