Twisted nanotubes spring into action. (Nanotechnology).

Carbon nanotubes have been formed into tiny springs for microscopic devices by researchers from the University of North Carolina at Chapel Hill, USA.

To make the nano-springs, the researchers combined an atomic force microscope with scanning electron microscopy to position tiny paddles on top of a nanotube. They used the paddles to force the nanotube to twist. The process of twisting the tubes stiffened them by as much as 20 times, an effect the researchers are currently working to explain.

The scanning electron microscope component allowed the researchers to see the paddles as they touched them with the atomic force probe, which is sensitive enough to measure the small forces needed to twist the nanotube.

The tiny springs could one day be used as chemical sensors and frequency sources for communications or computational electronics. However, the developers of the nano-springs admit that practical applications such as these are probably at least five years away.

For further information, contact: University of North Carolina at Chapel Hill, 210 Pittsboro Street, Campus, Box 6210, Chapel Hill, NC 27599-6210, USA; tel: +1-919-962-1185, fax: +1-919-962-2279; Internet: www.unc.edu