Domain Wall Magnetism in Multiferroic BiFeO3

Through a combination of theoretical calculations and experimental studies, a holistic picture of the connection between processing, structure, and properties brings to light the role of magnetism at ferroelectric domain walls in determining the magnetic properties in BiFeO$_{3}$. By controlling domain structures through epitaxial growth constraints and probing these domain walls with exchange bias studies, x-ray magnetic dichroism based spectromicroscopy, and high resolution transmission electron microscopy we demonstrate that the formation of certain types of ferroelectric domain walls (i.e., 109$^{\circ}$ walls) can lead to enhanced magnetic moments in BiFeO$_{3}$. This work is supported by the Department of Energy.