Spin Polarized effects at the interface between manganites and organic semiconductors.

Spintronics is a new branch of electronics based on purely quantum effects. Instead of carrier's charge transfer as in usual electronics, it evokes carrier's spin transfer. The search of new materials suitable for injecting and transferring carriers with a preferential spin orientation is of paramount importance for the development of spintronics. Here we report the results of the investigation of the spin polarization of the La0.7Sr0.3MnO3 manganite films and the spin polarized injection from the manganite into ?-conjugated organic semiconductors. The surface of the La0.7Sr0.3MnO3 films at room temperature is composed of homogeneous ferromagnetic (FM) phase in which paramagnetic (PM) defects are embedded. The ferromagnetic phase is highly spin polarized showing a room temperature half-metallic behavior. A strong magnetoresistance (up to 30%) was measured on nanostructured planar hybrid junctions LSMO/sexithiophene/LSMO indicating both the spin polarized injection and the spin polarized transport up to distances of about 100 nm at room temperature.