Nanotubes are sheets of carbon atoms rolled into a tube.
In different forms they can conduct electricity like a metal or can be semi-conducting. A team headed by Philip G Collins at IBM's Watson Research Center in New York state developed a method to control the conductivity of multi-walled nanotubes that connect electrodes. The group reported in last week's issue of the journal Science that they were able to selectively destroy some of the layers by running extremely high currents through them in air. In the second paper in the same journal, Min Ouyang and colleagues at Harvard University reported on studies of single-wall nanotubes. Variations in how the carbon atoms are rolled into the tube can give them different electronic properties.