Influence of crystal structure on charge carrier effective masses in BiFeO${}_3$

Abstract

Ferroelectric-based photovoltaics have shown great promise as a source of renewable energy, thanks to their in-built charge separation capability, yet their efficiency is often limited by low charge carrier mobilities. In this work, we compare the photovoltaic prospects of various phases of the multiferroic material BiFeO${}_3$ by evaluating their charge carrier effective masses using first-principles simulations. We identify a tetragonal phase with the promising combination of a large spontaneous polarisation and relatively light charge carriers. From a systematic study of the octahedral distortions present in BiFeO${}_3$, we explain the relationship between structure and effective masses in terms of the changes to the orbital character and overlap at the band edges that result from changes in the geometry. The findings in this study provide some design principles to engineer desired effective masses in BiFeO${}_3$ and similar materials through manipulation of their crystal structures in experimentally accessible ways.

arXiv comment12 pages, 10 figures

References in corpus (16)

• BoltzTraP. A code for calculating band-structure dependent quantities
• BoltzTraP2, a program for interpolating band structures and calculating semi-classical transport coefficients
• First-principles study of spontaneous polarization in multiferroic BiFeO${}_3$
• Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite
• Origin of magnetoelectric behavior in BiFeO${}_3$
• Very large spontaneous electric polarization in BiFeO3 single crystals at room temperature and its evolution under cycling fields
• Effect of epitaxial strain on the spontaneous polarization of thin film ferroelectrics
• Ferroelectric Materials for Solar Energy Conversion: Photoferroics Revisited
• Influence of strain and oxygen vacancies on the magnetoelectric properties of multiferroic bismuth ferrite
• Suppression of Octahedral Tilts and Associated Changes of Electronic Properties at Epitaxial Oxide Heterostructure Interfaces
• Strain-induced isosymmetric phase transition in BiFeO3
• First-principles predictions of low-energy phases of multiferroic BiFeO3
• A multiferroic on the brink: uncovering the nuances of strain-induced transitions in BiFeO${}_3$
• Impact of non-parabolic electronic band structure on the optical and transport properties of photovoltaic materials
• The importance of anisotropic Coulomb interaction in LaMnO${}_3$
• Effects of the Hubbard U on density functional-based predictions of BiFeO${}_3$ properties

Cited by in corpus (1)

• Crossover between bulk and interface photovoltaic mechanisms in ferroelectric vertical heterostructure