BiFeO$_3$ nanoparticles at low-temperature using atomistic simulations -- surface charge distribution and terminations

Abstract

This paper analyzes how the ferroelectric properties of cubic-like BiFeO$_3$ nanoparticles are affected by different terminations and charge distributions at the surface using ab-initio-based atomistic computational experiments. Our findings unveil multiple multidomain configurations and illustrate how the different order parameters evolve towards the surface. Interestingly, for neutral terminations, a non-rhombohedral phase of BiFeO$_3$ with a stripe-like polarization arrangement was stabilized. We evaluate the polarization, oxygen octahedra rotation, and volume variation for all the configurations obtained, taking advantage of the atomic-scale details provided by the methods used in this study.