Antisite defects in La0.7Sr0.3MnO3 and La0.7Sr0.3FeO3

Complex oxide thin films and superlattices with the perovskite ABO(3) structure have been found to possess multifunctional properties. Here, we present our discovery of antisite defects, La ions in Fe(Mn) sites (denoted as La-B), in a La0.7Sr0.3MnO3/La0.7Sr0.3FeO3 superlattice. The antisite defect was directly characterized by atomic resolution Z-contrast imaging and the composition and electronic structure were analyzed by electron energy loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Density functional theory was used to calculate the formation energy, showing that the formation of the detected antisite defects is a consequence of the slightly reducing conditions during sample growth. (C) 2013 AIP Publishing LLC [http://dx.doi.org/10.1063/1.4802210]