Structural, dielectric, and magnetic properties of epitaxially grown BaFeO3 thin films on (100) SrTiO3 single-crystal substrates

We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on (100) SrTiO3 substrates by pulsed laser-beam deposition. The reflection high-energy electron diffraction patterns for the films apparently show a C-4 symmetry operation, suggesting that the sample had a pseudocubic perovskite structure rather than hexagonal unit cell. The films were found to be highly insulating, and showed a high value of dielectric constant of epsilon=59. At 300 K, the magnetization loop of the film apparently shows hysteresis, as well as small remanent magnetization. These characteristics are totally different from those of bulk BaFeO3. (C) 2002 American Institute of Physics.