Enhanced magnetic parameters in the morphotropic phase boundary region of nanocrystalline multiferroic Bi1−xLaxFeO3

Antiferromagnetic multiferroic BiFeO3 shows ferromagnetic characteristics by simultaneous substitution of Bi by La and decrease in the particle size to nanometer dimensions. Large changes in saturation and remnant magnetization, magnetic susceptibility at low and high fields, along with some anomalous changes in the magnetic transition temperature are observed in nanocrystalline Bi1−xLaxFeO3 system for 0.1≤x≤0.20.1≤x≤0.2. This compositional region corresponds to the morphotropic phase boundary (MPB) region separating the rhombohedral and orthorhombic phases, and the effect is similar to that observed in many ferroelectric systems. The present observation of enhanced ferromagnetic parameters in the MPB region of the nanocrystalline multiferroic La substituted BiFeO3 system, combined with the known ferroelectric characteristics, is suitable for future device applications.

► Enhanced ferromagnetic characteristics for nanosized multiferroic Bi1−xLaxFeO3.
► Studies in the morphotropic phase boundary (MPB) region.
► Unusual and enhanced magnetic parameters in the MPB region.
► Anomalously large magnetic transition temperature in the MPB region.
► First report on such drastic changes of ferromagnetic system in the MPB region.