Organic semiconductors have proved to be very relevant electronic materials. Their greatest success has been undoubtedly achieved so far in the optoelectronics field, where display products based on hybrid light emitting diodes with organic emitter (OLEDs) have become available to consumers, and organic photovoltaic devices are challenging existing commercial applications.
These organic materials have recently caught the attention of spintronics, and significant efforts are being made towards their integration in this field. Their most attractive aspect for spintronic applications is the weakness of the spin scattering mechanisms in OSC, implying that the spin polarization of the carriers can be maintained for a very long time in these materials. Noticeably, spin relaxation times in excess of 10 microseconds have been reported by different resonance techniques, values exceeding by orders of magnitude the characteristic times detected in inorganic materials. Moreover, these materials have extremely tunable chemical properties, opening a way for the integration of synthetic chemistry into spintronic devices.
In this talk I shall focus on the major achievements and questions arising from electrical spin injection and transport in organic semiconductor materials. I will begin by presenting and discussing the concepts and facts which are widely accepted by the community and will conclude by addressing the most controversial issues and open questions. I will also make a comparison of this field with other recent advances in carbon spintronics (regarding carbon nanotubes and graphene).