Coherent magneto-elastic domains in multiferroic BiFeO3 films

TL;DR

This study reveals that epitaxial BiFeO3 films host coherent antiferromagnetic domains coupled with a monoclinic twin structure, differing from bulk crystals, and suggests strain-based control of magnetism in devices.

Contribution

It demonstrates the presence of magneto-elastic domains in BiFeO3 films and links them to a unique epitaxial twin structure not found in bulk crystals.

Findings

Epitaxial BiFeO3 films support sub-micron antiferromagnetic domains.

Domains are magneto-elastically coupled to a monoclinic twin structure.

This structure is absent in bulk single crystals, enabling strain-based magnetic control.

Abstract

The physical properties of epitaxial films can fundamentally differ from those of bulk single crystals even above the critical thickness. By a combination of non-resonant x-ray magnetic scattering, neutron diffraction and vector-mapped x-ray magnetic linear dichroism photoemission electron microscopy, we show that epitaxial (111)-BiFeO3 films support sub-micron antiferromagnetic domains, which are magneto-elastically coupled to a coherent crystallographic monoclinic twin structure. This unique texture, which is absent in bulk single crystals, should enable control of magnetism in BiFeO3 film devices via epitaxial strain.