Beyond the everlasting lightbulb

Gallium nitride is used to produce very bright light emitting diodes and lasers, and very high power transistors that can operate at high temperatures. Now, thanks to a £500,000 donation of equipment from the Cambridge-based Thomas Swan Scientific Equipment Ltd (TSSEL), researchers at Cambridge will be placed at the forefront of this new technology.

The Engineering and Physical Sciences Research Council has also provided a grant of almost £1 million for the running costs. The research programme will be conducted in partnership between TSSEL and the University of Cambridge along with University College London and the University of Manchester Institute of Science and Technology.

Professor Colin Humphreys, of the Department of Materials Science and Metallurgy, explained the importance of gallium nitride: ‘Light emitting diodes based on gallium nitride can be used to make light bulbs that last 100 times longer than traditional bulbs and consume only 10 per cent of their energy,’ he said. ‘If light bulbs are replaced by these LEDs, huge energy savings will result, with big reductions in CO2 emissions from power stations.’

‘Gallium nitride can also be used to make blue lasers that will write at least four times more information on CDs and optical disks than the red lasers we use at present. That means it will be possible to write all of Madonna’s melodies – or all of Schubert’s symphonies – on a single CD.’

Other potential applications for this technology include powerful transistors which can be used in mobile phone base stations to give much greater ranges of transmission, and highly accurate lasers which could be used in surgery and dentistry.