First-principles Landau-like potential for BiFeO${}_3$ and related materials

Abstract

In this work we introduce the simplest, lowest-order Landau-like potential for BiFeO${}_3$ and La-doped BiFeO${}_3$ as an expansion around the paraelectric cubic phase in powers of polarization, FeO${}_6$ octahedral rotations and strains. We present an analytical approach for computing the model parameters from density functional theory. We illustrate our approach by computing the potentials for BiFeO${}_3$ and La${}_{0.25}$Bi${}_{0.75}$FeO${}_3$ and show that, overall, we are able to capture the first-principles results accurately. The computed models allow us to identify and explain the main interactions controlling the relative stability of the competing low-energy phases of these compounds.

12 pages, 6 figures

References in corpus (7)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite
• Very large spontaneous electric polarization in BiFeO3 single crystals at room temperature and its evolution under cycling fields
• Structural distortion and magnetism of BiFeO3 epitaxial thin films: a Raman spectroscopy and neutron diffraction study
• First-principles based Landau-Devonshire potential for BiFeO${}_3$
• Comparative ab initio study of the structural, electronic, magnetic, and dynamical properties of LiOsO${}_3$ and NaOsO${}_3$

Cited by in corpus (1)

• A coupled magneto-structural continuum model for multiferroic ${\mathrm{BiFeO}}_3$