Perovskite solid solutions with multiferroic morphotropic phase boundaries and property enhancement

Recently,large phase-change magnetoelectric response has been anticipated by a first-principles investigation of phases in the BiFeO_(3)–BiCoO_(3)perovskite binary system,associated with the existence of a discontinuous morphotropic phase boundary(MPB)between multiferroic polymorphs of rhombohedral and tetragonal symmetries.This might be a general property of multiferroic phase instabilities,and a novel promising approach for room temperature magnetoelectricity.We review here our current inves-tigations on the identification and study of additional material systems,alternative to BiFeO_(3)–BiCoO_(3)that has only been obtained by high pressure synthesis.Three systems,whose phase diagrams were,in principle,liable to show multiferroic MPBs have been addressed:the BiMnO_(3)–PbTiO_(3)and BiFeO_(3)–PbTiO_(3)binary systems,and the BiFeO_(3)–BiMnO_(3)–PbTiO_(3)ternary one.A compre-hensive study of multiferroism across different solid solutions was carried out based on electrical and magnetic characterizations,complemented with mechanical and electromechanical measurements.An in-depth structural analysis was also accomplished when necessary.