Data transmission speed of 2.56 Tb/s achieved by twisting beams of light
By Darren Quick
June 26, 2012
Thankfully, data transmission speeds have come a long way since the days of dial-up when users would have plenty of time to twiddle their thumbs as they waited for an image or MP3 to make its way to their hard drive. These days, broadband cable currently supports speeds of around 30 megabits per second, which is a hell of an improvement. Now researchers have outdone that by a factor of around 85,000 by using twisted beams of light to transmit data at up to 2.56 terabits per second.
The system developed by the multi-national team led by the University of Southern California (USC) involved transmitting data twisted beams of light at ultra-high speeds. Using beam-twisted “phase holograms,” they manipulated eight beams of light so that each one twisted in a DNA-like helical shape as it propagated in free space. With each beam having its own twist that can be encoded with “1” and “0” data bits, they formed eight independent data streams.
Because the system could be used in high-speed satellite communication links, they attempted to simulate the sort of communications that might occur between satellites in space by transmitting data over open space in a lab. The system also has the potential to be used in short free-space terrestrial links, or to be adapted for use in fiber optic cables like those used by some Internet service providers.
While not quite at the world record-breaking data transmission speed of 26 terabits per second achieved last year by a team from Germany’s Karlsruhe Institute of Technology (KIT), the latest effort is still impressive.
“You’re able to do things with light that you can’t do with electricity,” said Alan Willner, electrical engineering professor at the USC Viterbi School of Engineering. “We didn’t invent the twisting of light, but we took the concept and ramped it up to a terabit-per-second.”
Willner is the author of an article about the research that was published in Nature Photonics on June 24.