Recent years witnessed increasing research for exploiting carbon-based materials as a spin transporting channel, which introduces a new avenue for device integration and functionality . Molecule/organic-based magnets, that allow chemical tuning of electronic and magnetic properties, are a promising new class of magnetic materials for future spintronics [2,3]. The advantages of using organic-based magnets as spin polarizers in spintronic applications include, chemical tunability, highly spin-polarized electronic nature , low temperature processing, optical control of magnetism and conductivity , etc. V(TCNE:tetracyanoethylene)<SUB><I>x</I></SUB> (<I>x</I> ~ 2) is the earliest developed room temperature molecule-based magnet . It has ferrimagnetic coupling between the spins in the TCNE π* orbital and spins in V<SUP>II</SUP> <I>d</I>(<I>t</I><SUB>2g</SUB>) orbital with <I>T</I><SUB>c</SUB> ~ 400 K. This material also can be grown as a thin film via low-temperature (40 °C) chemical vapor deposition (CVD) . Besides its robust room temperature magnetic ordering, the V(TCNE)<SUB><I>x</I></SUB> has unique electronic structure, as a ‘half-semiconductor’ , i.e., fully spin polarized non-overlapping valence and conduction bands The highly spin polarized electronic state was observed by magnetic circular dichroism . In this talk, we present realization of an organic-based magnetic/non-magnetic semiconductor as an electron spin polarizer/spin transporting layer in the standard spintronic device geometry [1,9]. The application of organic small molecule films as the spin transporting layer has been studied recently However, conceptual understanding of how the spins are injected into and transport through these organic semiconductor films was missing. With careful study on film thickness, temperature, and bias dependencies, significant differences between tunneling and giant magnetoresistance were resolved . In addition, the room tempearture organic-based magnet, V(TCNE)<SUB><I>x</I></SUB> was successfully incorporated into the standard magnetic tunnel junction device . Our results unambiguously demonstrates spin filtering of current passing through a V(TCNE)<SUB><I>x</I></SUB> magnetic semiconductor film, with sebsequent tunneling of the spin polarized carriers through a the hybrid rubrene/LAO barrier while effectively conserving spin polarization. A detailed discussion on temperature dependence and applied bias dependence will be presented.
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