Organic spin valves open up to neutrons
11 Nov 2009




Electronic devices that utilise atomic-level spins – as opposed to charge – hold unique prospects for future technology.

A spintronic device of the sort already used in hard drive read heads and magnetic memory: the spin valve. A spin polarised current is injected from a magnetic layer (green) into a non-magnetic spacer layer (yellow), where the spin polarisation is reduce

They promise low-power logic, possibly at the quantum level, and the combination on the same chip of communication, logic and memory elements. When such spintronic devices include use of organic materials, which have low manufacturing costs and are mechanically flexible, there is considerable further potential for extending the scope that these devices have. This may lead to an entirely new generation of spin-enabled electronics. However, the mechanisms behind spin injection and transport in organic materials are not well known, as there is a severe lack of suitable experimental techniques. Using spin polarised neutron reflectivity, we have imaged the injected spin polarisation and its transport away from a buried interface within a fully functional and realistic device. The results highlight the unique potential of the technique to reveal the mechanisms that limit the spin coherence within devices, especially in those involving organic materials. Specifically, it can enable bulk and interface-related spin decoherence phenomena to be differentiated.

AJ Drew (Queen Mary University of London), L Schulz (University of Fribourg), S Langridge (ISIS)


Contact: Dr Alan Drew,

Further reading: AJ Drew et al., Nature Materials 8 (2009) 109