The future of bugging hangs by a thread of light

Thursday 28 April 2005

A Melbourne University research team has developed technology that will ultimately make it impossible to eavesdrop on communications and steal information—and it all depends on growing diamonds in a microwave oven.

This new technology could represent a boom for the financial institutions, security agencies, governments and individuals who need to communicate sensitive information with total security, says Fresh Innovator James Rabeau.

Most information these days is sent via fibre optics. Sending such information from A to B with absolute, uncrackable security depends on the unique properties of light, says Dr Rabeau.

Light beams are made up of billions of particles, known as photons. At present, it is possible to divert or tap off some of the photons from a light beam and reconstruct the information they represent.

But if the information were carried by a stream of single photons, then removing any would both corrupt the information and break the communication thread.

The eavesdropper would end up with no useful information, and the sender and receiver would instantly know they were being bugged.

“The biggest limitation confronting this technology has been the lack of a cheap and reliable light source with the adaptations necessary to produce the single-photon light beam,” Dr Rabeau says. And that’s the problem his team has solved.

The patented invention involves souped up microwave oven technology to grow tiny diamond particles onto the tips of optical fibres.

The result is a device which generates the critical single light particles.

Already two companies are making and selling the equipment necessary for this type of cryptography, but the light sources they use are inadequate. The diamond device invented in Melbourne is the front runner to replace the existing sources. 

Rabeau and his colleagues at the University of Melbourne’s School of Physics recently received a $3.3 million innovation grant from the Victorian government to develop a prototype device and commercialise the technology. (www.innovation.vic.gov.au)

Rabeau’s innovation has won him a place at Fresh Innovators—a national initiative to bring the work of 16 early-career inventers to public attention. After training in Sydney, the Innovators are talking to the media, schools and business about their ideas. One of the 16 will win a study tour to the UK courtesy of the British Council Australia.

For more information contact James Rabeau m: 0425 826 137 e: jrabeau@physics.unimelb.edu.au