Beams of light and modern optical networks send 10 gigabits of information per second. However, the processing speed is struggling to catch up. Daniel Gauthier, at Duke University in Durham, North Carolina, and his colleagues have demonstrated a possible solution. The information in a beam of light can be stored for a while by converting it into a sound signal, then reading it back out again as light, researchers have found. The process, which can be done in commercially-available optical fibers, could be used to help make computer processing more efficient in future. Here is what they discovered:
They first send optical data as a stream of light pulses into a short piece of standard optical fibre. Into the other end of the fibre they send a different short pulse: the 'write' pulse. When the two sets of pulses collide, they interfere, and an interference pattern is set up in the fibre with areas of high and low intensity. This interference pattern in turn affects the physical properties of the fibre, setting up an acoustic wave because of a phenomenon called electrostriction.As the light pulse leaves the fibre, the acoustic wave with all its inherited information lags behind: the speed of light in the fibre, at some 200 million metres per second, far exceeds the more sluggish 5,000 metres per second of sound. “The acoustic wave is essentially stationary over the duration of our experiment,” says Gauthier, whose work is published in Science 1.
To get the information from the acoustic wave out again, a third light pulse, the 'read' pulse, is sent in. When it reaches the part of the fibre being affected by the acoustic wave, the light scatters in such a way as to regain the information that was left behind by the initial pulse. The newly-formed data pulse leaves the fibre, resuming the journey in the same direction as the original pulse, taking the same information with it.
The power needed for their discovery is high and would evaporate some systems. However, with a little money and time, the future of this technology looks bright. It is absolutely incredible to me that this is even possible. Although light and sounds are both forms of energy, converting light into sound just seems to be a little crazy but very cool.