Many materials scientists predict that the tiny, hollow cylinders of carbon atoms known as carbon nanotubes will eventually lead to a new generation of supersmall transistors. But first, researchers will need to join nanotubes together.
A new welding technique may be the answer. Pulickel M. Ajayan of Rensselaer Polytechnic Institute in Troy, N.Y., and his colleagues have managed to join pairs of so-called single-walled carbon nanotubes into structures that resemble Xs, Ys, and Ts.
He and his coworkers made the structures by first identifying overlapping nanotubes in a sample under a transmission electron microscope. When they bombarded the nanotubes with electrons and applied heat, carbon-carbon bonds broke apart and reformed between the overlapping tubes where they touched.
Carbon nanotubes come in two forms: the single-walled variety, which is characterized by a cylinder of carbon with walls just one atom thick, and a multiple-walled variety marked by several tu