Energy beam discovery sends Austrian researchers round the twist

12 Nov 2014

In a world first, Austrian researchers have successfully transported data through twisted beams of light across a 3-kilometre stretch of Vienna.

This development could enable researchers to profit from potentially significant data-carrying properties of light.

The key to this discovery is the use of twisted light, rather than a standard single beam light. Research has shown that corkscrew-shaped light increases the number of channels in which data can be transmitted.

“Instead of using one wavelength of light as one channel of communication, the light can be theoretically twisted with an infinite number of turns, with each configuration acting as a single communication channel,” reports Phys.Org

“This twisting characteristic, known as orbital angular momentum (OAM), has been exploited by researchers in the past, with some showing that it can be used to transmit 2.5 terabits of data per second – the carrying capacity of more than 66 DVDs – through an optical fibre.”

The fact optical fibres are not always an ideal transporter has made researchers look at alternatives, such as twisted light, travelling through ever-changing air space.

Co-author of study Mario Krenn said, “We have shown for the first time that information can be encoded onto twisted light and sent through a 3-kilometre intracity link with strong turbulences.

“The OAM of light is theoretically unbounded, meaning that one has, in theory, an unlimited amount of different distinguishable states in which light can be encoded. It is envisaged that this additional degree of freedom could significantly increase data rates in classical communication.”

This study, published in the Institute of Physics and German Physical Society’s New Journal of Physics, saw researchers send a green laser beam from the radar tower at the Central Institute of Meteorology and Geodynamics in Vienna to a receiver in the University of Vienna, 3 kilometres away, explained in the video below.

Twisted lights image via Shutterstock

Gordon Hunt was a journalist with Silicon Republic