Multiferroicity and 180° magnetization switching in LaFeO3 via antisite defects

Here we show, using density functional theory calculations, that introducing Fe La antisite defects into pristine, non-ferroelectric, G-type antiferromagnetic (AFM) LaFeO 3 renders the material simultaneously ferroelectric and a defect-induced local ferrimagnetic phase. We assess the thermodynamic stability of Fe La antisites and identify synthesis conditions under which they are likely to form.

Nudged elastic band calculations indicate an accessible barrier for ferroelectric polarization switching. Interestingly, we observe an inverse magnetoelectric coupling in which the ferroelectric polarization controls the magnetic order. We further propose two defect-mediated magnetization-control mechanisms enabled by ferroelectric switching in LaFeO 3 , both involving a 180° reversal: (i) switching the Fe La antisite moments while the pristine G-type AFM order remains unchanged, and (ii) of the pristine G-type AFM order while the Fe La antisite moments are pinned by a static magnetic field.