November 2011

Researchers from China's Fudan University say that graphene nanoribbons could potentially be used to create spin valves. They present a theoretic spin valve design that uses two hexagonal graphene "nanoislands" with zig-zag edges, which serve as the magnetic layers in the spin valve, connected by an armchair-type nanoribbon as the non-magnetic layer, through which the electrons can pass depending on the relative alignment of the spins in the nanoislands.

They calcualte that this design enables stable spin configurations at certain energies, and there will be stable configurations in which the islands are polarized either parallel or antiparallel with respect to each other — a necessary requirement for a spin valve.

Researchers from the Trinity College in Dublin, Ireland, found out that Organic molecules can exhibit n-type magnetism. They say that conjugated polymers make strong candidates for future spintronic applications.

While organic compounds are interesting for spintronics due to their extremely long spin lifetimes (because of weak spin relaxation effects), it's not very easy to manipulate the spin orientation in organic spin devices. The new class of molecules (known as spin crossover compounds) may solve this issue as their spin state can be changed from low spin to high spin by an external perturbation.