Lasers are awesome. The laser was once the stuff of fiction and today we use lasers for all sorts of cool things. We can burn things with them, the military is using them for weapons, and some researchers are using the laser to transfer data much faster than wires can. The world record for shooting data down a path with lasers is 101.7 terabits per second. That record setting system used a whopping 370 separate lasers making it expensive and impractical with today's laser tech.
Professor Wolfgang Freude and his colleagues have announced a new world record for transmitting data with a single laser. The team was able to hit 26 terabits per second with the one laser. Each pulse of the laser used in the demonstration has about 325 different colors of light and each light color can carry a bit of data. The team was able to shoo the data down a length of optical fiber 50km long and then extract the different colors using a fast Fourier transform at the opposite end.
That algorithm can extract the different colors from the beam based on the number of times different parts of the beam arrive. Part of the success of Freude and the team of researchers was that they were able to split their data packing laser beam optically rather than mathematically. The optical split allows various parts of the beam to arrive at different times. The data can then be separated into bits and put back together.