A combined theoretical and experimental study of the phase coexistence and morphotropic boundaries in ferroelectric-antiferroelectric-antiferrodistortive multiferroics

The physical nature of the ferroelectric (FE), ferrielectric (FEI) and antiferroelectric (AFE) phases, their coexistence spatial distributions underpins functionality antiferrodistortive (AFD) multiferroics in vicinity morphotropic phase transitions. Using Landau-Ginzburg-Devonshire (LGD) phenomenology a semi-microscopic four sublattice model (FSM), we explore behavior different AFE, FEI, FE long-range orderings at boundaries FE-AFE-AFD multiferroics. These theoretical predictions are compared with experimental observations for dense Bi1-yRyFeO3 ceramics, where R is Sm or La atoms fraction 0 ≤ y 0.25, as confirmed by X-ray diffraction (XRD) Piezoresponse Force Microscopy (PFM). complementary measurements were used to study macroscopic nanoscopic transformation crystal structure doping. comparison measured calculated AFE/FE fractions demonstrate that LGD-FSM approach well describes results obtained XRD PFM Bi1-yRyFeO3. Hence, this combined provides further insight into origin coexisting AFE states rare-earth doped