Temperature and thickness evolution and epitaxial breakdown in highly-strained BiFeO3 thin films

Abstract

We present the temperature- and thickness-dependent structural and morphological evolution of strain induced transformations in highly-strained epitaxial BiFeO3 films deposited on LaAlO3 (001) substrates. Using high-resolution X-ray diffraction and temperature-dependent scanning-probe-based studies we observe a complex temperature- and thickness-dependent evolution of phases in this system. A thickness-dependent transformation from a single monoclinically distorted tetragonal-like phase to a complex mixed-phase structure in films with thicknesses up to ~200 nm is the consequence of a strain-induced spinodal instability in the BiFeO3/LaAlO3 system. Additionally, a breakdown of this strain-stabilized metastable mixed-phase structure to non-epitaxial microcrystals of the parent rhombohedral structure of BiFeO3 is observed to occur at a critical thickness of ~300 nm. We further propose a mechanism for this abrupt breakdown that provides insight into the competing nature of the phases in this system.

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References in corpus (8)

• Origin of magnetoelectric behavior in BiFeO${}_3$
• Room temperature coexistence of large electric polarization and magnetic order in BiFeO3 single crystals
• Effect of epitaxial strain on the spontaneous polarization of thin film ferroelectrics
• Stress-induced R-MA-MC-T symmetry changes in BiFeO3 films
• Low-Symmetry Monoclinic Phases and Polarization Rotation Path Mediated By Epitaxial Strain in Multiferroic BiFeO3 Thin Films
• Singe ferroelectric and chiral magnetic domain of single-crystalline BiFeO${}_3$ in an electric field
• Phase transition close to room temperature in BiFeO3 thin films
• Anomalous low-energy phonons in nearly tetragonal BiFeO3 thin films

Cited by in corpus (6)

• A multiferroic on the brink: uncovering the nuances of strain-induced transitions in BiFeO${}_3$
• Super-R BiFeO${}_3$: Epitaxial stabilization of a low-symmetry phase with giant electromechanical response
• Nanosecond Optically Induced Phase Transformation in Compressively Strained BiFeO3 on LaAlO3
• Domain tuning in mixed-phase BiFeO3 thin films using vicinal substrates
• Combined electrostatic and strain engineering of BiFeO${}_3$ thin films at the morphotropic phase boundary
• An empirical approach to measuring interface energies in mixed-phase bismuth ferrite