A small ribbon made of the carbon honeycomb pattern found in graphite and nanotubes could display intriguing electronic properties and serve as a material for spin-based electronics (spintronics), researchers have predicted.

Steven Louie's group at the University of California at Berkeley, US, has now used ab initio calculations to show that ceratain carbon nanoribbons will display half-metallicity. The researchers calculated the electronic properties of graphene sheets (the single layers of hexagonally arranged carbon atoms found in graphite). Specifically, they looked at ribbons between 1.5 and 6.7 nm wide,  with a zigzag border at each side (see image below).

The researchers found that such ribbons, if subjected to an electric field perpendicular to the ribbon length, should display half-metallic properties. They even predict that these properties should be robust against imperfections of the border structure. 

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