Transporting data across computer chips can be done without electricity: researchers have successfully achieved the same by using light. The new study shows how data transmission can be made to be much faster, and simultaneously using up less energy.
Even if we can send data in the form of photons through optical fibres on the Internet, we have so far still used electricity once the data reaches our computers; the data makes the transition from an extremely fast transmission mode to a considerably slower one as it needs to be converted into electrons to get into the device. This requires much energy, some of which is released as heat (hence why computers are hot).
One of the authors of the study, Jelena Vuckovic from Stanford University in the US, explains how energy-consuming this process is:-
“Up to 80 percent of the microprocessor power is consumed by sending data over the wires,” said Vuckovic in a statement.
The engineers have managed to transmit light across the different connections between computer chips. They have come up with a solution to one of the obstacles hindering researchers from doing so in the past. To beam light between chips would previously require silicon structures to bend the light to the desired spot to replace all wires in a computer. Now, the team of scientists have created an inverse design algorithm that dictates how to construct the silicon structures to do the job.
The algorithm has already been put to use to make an optical circuit, of which several copies have been made in lab.
The new devices have been shown to operate well in spite of certain imperfections.
“Our manufacturing processes are not nearly as precise as those at commercial fabrication plants,” said one of the researchers behind the algorithm, Alexander Piggott. “The fact that we could build devices this robust on our equipment tells us that this technology will be easy to mass-produce at state-of-the-art facilities.”
The slices of silicon have been layered. They are extremely thin: more than 20 of them could fit within the diameter of a single human hair. The silicon pieces are carefully arranged as per the algorithm, and as light passes through them, it bends, such that switches were made, controlling the flow of photons. This works similar to wires directing the flow of electrons.
“Our structures look like Swiss cheese but they work better than anything we’ve seen before,” said Vuckovic.