The world's tiniest radio?

Claimed to be smaller than a grain of sand

8 February 2008 15:59 GMT / By Katie Scott

Researchers in the US have made a tiny radio from carbon nanotubes.

These tiny strands of carbon atoms are smaller than a grain of sand but the team behind the project claim that they may end up outperforming current silicon-based electronics.

"Our goal is not to make tiny radios per se, but really to develop nanotubes as a higher-performing semiconductor", said John Rogers, a professor of materials science and engineering at the University of Illinois to Reuters.

The devices are specifically hoped to showcase a new way of making carbon nanotubes in perfectly aligned rows, adds the news service.

Reuters add that the strands are a hundred thousand times smaller than the width of a human hair, forming a thin layer of semiconductor material that can be used in electronics devices and circuits.

"The radio is really a step along the path to building new platforms for electronics technology", adds Rogers.

"We're interested in nanotubes not because they are small but because smallness imparts some electronic properties that are very appealing, meaning you could make a faster device."

This team has concentrated on controlling the shapes the tubes take when they are made by combining carbon and heat and a catalyst on a special quartz wafer.

Once they have made the tubes, the rest of the process is said to be like that used to make electronics using normal silicon chips.

The nanotubes were then tested in two radio frequency amplifiers, a radio frequency mixer and an audio amplifier, all made from the carbon nanotube materials.

The testers plugged in regular-sized headphones into an output transistor made from the nanotube material, and also used a normal-sized antenna.

Reuters reports that in one test, the researchers tuned one of the nanotube-transistor radios to a Baltimore radio station and picked up the traffic report.

Rogers concluded: "The radio itself is not interesting. But the fact that we are at a point that we can do things like a radio is a good milestone for us."

Full tags

Audio, Radios, Gadgets