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Abstract: We report on the growth of magnetite films directly on thin layers of organic semiconductors by means of an electron beam ablation method. The deposition was performed at room temperature in a reactive plasma atmosphere. Thin films show ferromagnetic (FM) hysteresis loops and coercive fields of hundreds of Oersted. Micro Raman analysis indicates no presence of spurious phases. The morphology of the magnetite film is strongly influenced by the morphology of the underlayer of the organic semiconductor. These results open the way for the application of magnetite thin films in the field of organic spintronics. [Copyright &y& Elsevier]

Abstract: La0.7Sr0.3MnO3 polycrystalline manganite thin films were grown on silicon (Si) substrates covered by SiO x amorphous native oxide. Curie temperatures of about 325K were achieved for 70-nm-thick films. Strong room temperature XMCD signal was detected indicating high spin polarization at the surface. Cross-sectional TEM images show sharp interface between SiO x and manganite without signature of chemical reaction at the interface. Unusual sharp splitting of the manganite film was observed: on the top of a transition layer characterized by low crystalline order, a magnetically robust layer is formed. [Copyright &y& Elsevier]

Abstract: Magnetic and morphological properties of Cobalt thin films grown by RF sputtering on organic Alq3 layers were investigated by magneto-optical Kerr effect (MOKE) technique and atomic force microscopy (AFM). The AFM images indicate a template growth of Co layers on top of Alq3, the magnetic film “decorates” the surface of organic material. This peculiar morphology induces a strong uniaxial magnetic anisotropy in the Co films, as detected by MOKE measurements. Results are important for the operation of a new class of devices-vertical organic spin valves. [Copyright &y& Elsevier]

Abstract: Ultrathin ferromagnetic films of La0.7Sr0.3MnO3 were deposited by electron-beam ablation on standard SrTiO3(100) and NdGaO3(110) substrates. Even 4nm films are metallic and develop spontaneous magnetization at room temperature: similar hysteresis cycles were measured by magneto optical Kerr effect (MOKE) in the longitudinal configuaration and by SQUID magnetometry. To the best of our knowledge the 4nm thickness corresponds so far to the thinnest manganite film showing room-temperature ferromagnetism. [Copyright &y& Elsevier]