First-Principles Investigation of Morphotropic Transitions and Phase-Change Functional Responses inBiFeO3−BiCoO3Multiferroic Solid Solutions

Abstract

We present an ab initio study of the BFCO solid solution formed by multiferroics ${\mathrm{BiFeO}}_3$ (BFO) and ${\mathrm{BiFeO}}_3$ (BCO). We find that BFCO presents a strongly discontinuous morphotropic transition between BFO-like and BCO-like ferroelectric phases. Further, for all compositions such phases remain (meta)stable and retain well-differentiated properties. Our results thus suggest that an electric field can be used to switch between these structures and show that such a switching involves large phase-change effects of various types, including piezoelectric, electric, and magnetoelectric ones. DOI: http://dx.doi.org/10.1103/PhysRevLett.107.057601 © 2011 American Physical Society