Tuning the magnetic characteristics of epitaxial BiFeO3 films using structural control

Epitaxial BiFeO3 thin films with different thicknesses were grown on SrTiO3 (001) substrate. The film exhibits a structural transformation from “R-like” phase with out-of-plane lattice parameter 4.06 Å to a “T-like” phase with out-of-plane lattice parameter 4.65 Å on increasing the thickness from 16 nm to 60 nm. The parasitic γFe2O3 phase was avoided by using slightly higher oxygen pressure during the growth. The “R-like” phase is shown to exhibit significant magnetic anisotropy and enhanced saturation magnetization which vanishes with the appearance of the “T-like” phase.