Organic light emitting diodes with spin polarized electrodes

Electrical and optical properties of ${\mathrm{Alq}}_3$ based organic light emitting diodes with normal and spin polarized electrodes are presented. Epitaxial semitransparent highly spin polarized ${\mathrm{La}}_{\text{0.7}}{\mathrm{Sr}}_{\text{0.3}}{\mathrm{MnO}}_3$ were used as hole injector, substituting the traditional indium tin oxide electrode. A comparison of electroluminescence and $\mathrm{IV}$ curves between similar devices with and without spin polarized injection is reported. The results are a first step in realizing an operating device where the light intensity of the emission can be tuned by controlling the spin injection.