It is one of the smallest race tracks in the world - but it could hold the key to a big step forward in science and medicine. The 'track' at Durham University's department of physics is made up of a wire so small that 400 of them together would only be the thickness of a human hair. The length of the track is equally infinitesimal - just 20 one-millionths of a metre. But the scientists who created it believe it could point the way forward in the pioneering fields of nanotechnology - or miniaturisation - and spintronics, the science of mixing magnetism and electronics. Combining the two opens the way for tiny magnetic microchips, more energy efficient than the electronic version, that don't overheat or lose their memory when the power is switched off. These low-power chips could be used in everything from mobile phones and laptop computers to space travel, with the result that batteries would last longer. And they could also be planted in the human body to power pacemakers and monitors without the need for wire poking through the skin. All this has been made possible because of the speed at which the Durham physicists have been able to send magnetic charges down their tiny track. Dr Russell Cowburn, the team leader, said: "It was thought very small scale technology might be slow. "But we can now demonstrate that small can be fast." The test, which took a year to set up, saw the scientists use the track to send a magnetic charge at 3,400mph, compared to a previous fastest speed of 620mph. This is the equivalent of switching from travelling in a conventional jet aircraft to one flying at two and a half times the speed of Concorde. The problem with current chips is they need to be powered, which would involve either wires inserted through skin or replacement by operation. But the new chips could be fuelled simply by a magnetic coil outside the body. They could also be used for conditions such as diabetes, where people can lead normal lives but where monitoring is required for insulin to be released automatically into the body. It also has implications for quantum computing, potentially making systems faster than at present. The team has formed a company called Durham Magneto Optics Ltd to help with the manufacture of equipment behind the next generation of microchips. "Nanotechnology has been described as the next Industrial Revolution and every industrial revolution needs the tools," said Dr Cowburn. | 
