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A novel mechanism of ferroelectricity driven by off-centering magnetic Mn4+ions was proposed in (Sr1–xBax)MnO3, in its ideal perovskite phase, which yields enormous expectations in the search for strong magnetoelectric materials. Still, the desired perovskite phase has never been stabilized in thin films due to its extremely metastable character. Here, we report on a thorough study of the perovskite phase stabilization of (Sr1–xBax)MnO3thin films, 0.2 ≤ x≤ 0.5, grown by pulsed laser deposition onto (001)-oriented perovskite substrates. X-ray diffraction measurements and scanning transmission electron microscopy reveal that, under appropriate deposition conditions, the perovskite phase is fully stabilized over the nonferroelectric hexagonal phase, despite the latter being increasingly favored on increasing Ba-content. Moreover, we have managed to grow epitaxial coherent cube-on-cube (Sr1–xBax)MnO3films upon strains ranging from 0% to 4%. Our results become a milestone in further studying perovskite (Sr1–xBax)MnO3thin films and pave the way for tailoring ferroic and magnetoelectric properties either by strain engineering or Ba-doping.

We report magnetic and electronic transport measurements across epitaxial bilayers of ferromagnetic insulator LaCoO3and half-metallic ferromagnet La2/3Sr1/3MnO3(LCO/LSMO: 3.5 nm/20 nm) fabricated by a chemical solution method. The I–Vcurves at room temperature and 4K measured with conducting atomic force microscopy (CAFM) on well-defined patterned areas exhibit the typical features of a tunneling process. The curves have been fitted to the Simmons model to determine the height (φ) and width (s) of the insulating LCO barrier. The results yield φ = 0.40 ± 0.05 eV (0.50 ± 0.01 eV) at room temperature (4K) and s= 3 nm, in good agreement with the structural analysis. Our results demonstrate that this chemical method is able to produce epitaxial heterostructures with the quality required for this type of fundamental studies and applications.