Tuning polarization and elasticity properties by uniaxial stress in BiFeO3

TL;DR

This study uses density functional theory to analyze how uniaxial stress along [111] affects the polarization and elastic properties of BiFeO3, revealing near-linear polarization changes and elastic behavior useful for device applications.

Contribution

First comprehensive theoretical analysis of uniaxial stress effects on both polarization and elasticity in BiFeO3 using DFT methods.

Findings

Polarization of 87.5 ?C/cm² consistent with experiments

Polarization varies near-linearly under ±8 GPa stress

Elastic stiffness and compliance coefficients are characterized

Abstract

The changes of polarizational, elastic and structural properties of mutiferroic BiFeO3 under [111] direction uniaxial stress are calculated using density functional theory within the Perdew-Burke- Ernzerhof revised for solids (PBEsol) + U approach, and compared with available measurements or predictions. A large ferroelectric polarization of 87.5 ?C=cm2 is found, agreeing with other theoretical and experimental values, and the polarization changes near-linearly within the uniaxial stress range of 8 GPa to -8 GPa. This property can be used to indirectly control the radiative recombination of luminous organ and the electrical properties of transistor structure. In addition, we have also investigated the elastic stiffness coefficients and the elastic compliance coefficients in the same uniaxial stress range, which provide helpful guidance for the applications of BiFeO3.