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Resonant soft x-ray absoiption measurements at the O K edge on a SrMnO3/LaMnO3 superiattice show a shoulder at the energy of doped holes, which corresponds to the main peak of resonant scattering from the modulation in the doped hole density. Scattering line shape at the Mn L3.2 edges has a strong variation below the ferromagnetic transition temperature. This variation has a period equal to half the superiattice superperiod and follows the development of the ferromagnetic moment, pointing to a ferromagnetic phase developing at the interfaces. It occurs at the resonant energies for Mn3+ and Mn4+ valences. A model for these observations is presented, which includes a double-exchange two-site orbital and the variation with temperature of the hopping frequency tij between the two sites. [ABSTRACT FROM AUTHOR]

We have fabricated oxide-based spin-filter junctions in which we demonstrate that magnetic anisotropy can be used to tune the transport behavior of spin-filter junctions. We have demonstrated spin-filtering behavior in La0.7Sr0.3MnO3/CoCr2O4/Fe3O4 and La0.7Sr0.3MnO3/MnCr2O4/Fe3O4 junctions where the interface anisotropy plays a significant role in determining transport behavior. Detailed studies of chemical and magnetic structure at the interfaces indicate that abrupt changes in magnetic anisotropy across the nonisostructural interface is the cause of the significant suppression of junction magnetoresistance in junctions with MnCr2O4 barrier layers. [ABSTRACT FROM AUTHOR]

(LaNiO3)n/(LaMnO3)2 superlattices were grown using ozone-assisted molecular beam epitaxy, where LaNiO3 is a paramagnetic metal and LaMnO3 is an antiferromagnetic insulator. The superlattices exhibit excellent crystallinity and interfacial roughness of less than one unit cell. X-ray spectroscopy and dichroism measurements indicate that electrons are transferred from the LaMnO3 to the LaNiO3, inducing magnetism in LaNiO3. Magnetotransport measurements reveal a transition from metallic to insulating behavior as the LaNiO3 layer thickness is reduced from five to two unit cells and suggest an inhomogeneous magnetic structure within LaNiO3. [ABSTRACT FROM AUTHOR]