Quantum leap

Scientists have used the approach to directly calibrate a detector that can sense the presence of multiple individual photons, it is revealed in research published in Nature Physics. Being able to sense the presence of individual photons is an important requirement for the development of future long distance quantum communication devices and networks. One of the potential applications of this new detector is in devices for secret communications, which could allow information to be exchanged in total security guaranteed by the laws of physics, with no possibility of interception, or eavesdropping. One of the research team, Prof Martin Plenio, explained: "If you can detect the presence of light at the individual photon level you make it impossible for any information being transmitted as light energy to go astray, unnoticed, en route from transmitter to detector. An exciting development in the future could be to use this fundamental science to ensure that information and messages are transported across long distances with absolute security, and reach their destination without being tampered with."