The beta Phase of Multiferroic Bismuth Ferrite and its beta-gamma Metal-Insulator Transition

Abstract

We show that epitaxial (001) thin films of multiferroic bismuth ferrite BiFeO3 are monoclinic at room temperature instead of tetragonal or Rhombohedral as reported earlier . We report a orthorhombic order-disorder beta-phase between 820C and 950C contrary to the earlier report. The transition sequence monoclinic-orthorhombic phase in (001)BiFeO3 thin film (rhombohedral-orthorhombic transition in single crystal) resembles that of BaTiO3 or PbSc1/2Ta1/2O3. The transition to the cubic $\gamma$-phase causes an abrupt collapse of the bandgap toward zero (insulator-metal transition) at the orthorhombic-cubic beta-gamma transition around 950C. This transition is similar to the metal-insulator transition in Ba0.6K0.4BiO3.

5 Pages, 5 grphs

References in corpus (4)

• 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
• Room temperature coexistence of large electric polarization and magnetic order in BiFeO3 single crystals
• Influence of strain and oxygen vacancies on the magnetoelectric properties of multiferroic bismuth ferrite

Cited by in corpus (17)

• Suppression of Octahedral Tilts and Associated Changes of Electronic Properties at Epitaxial Oxide Heterostructure Interfaces
• The ferroelectric-paraelectric phase transition in BiFeO3: crystal structure of the orthorhombic beta-phase
• Structure and spin dynamics of multiferroric BiFeO${}_3$
• Effect of Structural Transition on Magnetic and Dielectric Properties of La and Mn co-substituted BiFeO3 Ceramics
• Ultrafast carrier dynamics and radiative recombination in multiferroic BiFeO${}_3$
• Effect of Rhombohedral to Orthorhombic Transition on Magnetic and Dielectric Properties of La and Ti co-substituted BiFeO3
• Photostriction in BiFeO3: wavelength dependence
• Laser-diode-heated floating zone (LDFZ) method appropriate to crystal growth of incongruently melting materials
• Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry
• Light controlled magnetoresistance and magnetic field controlled photoresistance in CoFe film deposited on BiFeO3
• Infrared and magnetic characterization of the multiferroic Bi2FeCrO6 thin films in a broad temperature range
• Phase Transitions and Antiferroelectrivity in BiFeO3 from Atomic Level Simulations
• On the link between Octahedral Rotations and Conductivity in the Domain Walls of BiFeO3
• Comparison the optical properties for Bi2O3 and NiO ultrathin films deposited on different substrates by DC sputtering technique for transparent electronics
• Non-thermal fluence threshold for femtosecond pulsed x-ray radiation damage in perovskite complex oxide epitaxial heterostructures
• Simplified approach to the magnetic blue shift of Mott gaps
• An analysis of derivative absorption spectroscopy of multiferroic bismuth ferrite materials