Spin relaxation in a nanowire organic spin valve: Observation of extremely long spin relaxation times

摘要

We report spin valve behavior in an organic nanowire consisting of threelayers - cobalt, Alq3 and nickel - all nominally 50 nm in diameter. Based onthe data, we conclude that the dominant spin relaxation mechanism in Alq3 isthe Elliott-Yafet mode. Despite the very short momentum relaxation time, thespin relaxation time is found to be very long - at least a few milliseconds -and relatively temperature independent up to 100 K. To our knowledge, this isthe first demonstration of an organic nanoscale spin valve, as well as thefirst determination of the primary spin relaxation mechanism in organics. Theunusually long spin relaxation time makes these materials ideal platforms forsome areas of spintronics.