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arXiv · 1005.3991

Spin injection and perpendicular spin transport in graphite nanostructures

T. Banerjee·W. G. van der Wiel·R. Jansen
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Abstract

Organic and carbon-based materials are attractive for spintronics because their small spin-orbit coupling and low hyperfine interaction is expected to give rise to large spin-relaxation times. However, the corresponding spin-relaxation length is not necessarily large when transport is via weakly interacting molecular orbitals. Here we use graphite as a model system and study spin transport in the direction perpendicular to the weakly bonded graphene sheets. We achieve injection of highly (75%) spin-polarized electrons into graphite nanostructures of 300-500 nm across and up to 17 nm thick, and observe transport without any measurable loss of spin information. Direct visualization of local spin transport in graphite-based spin-valve sandwiches also shows spatially uniform and near-unity transmission for electrons at 1.8 eV above the Fermi level.

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T. Banerjee, W. G. van der Wiel, R. Jansen. 2010-05-21. Spin injection and perpendicular spin transport in graphite nanostructures. https://doi.org/10.1103/physrevb.81.214409

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