Optical-to-acoustic microchip could boost data-center efficiency

Optical data can be too fast for its own good. While the speeds obtained are great for carrying information over distances and into chips, when the light-carried data lands there it’s often moving too fast to be thoroughly processed and analyzed. Data can need slowing down for intense number-crunching and routing.

Solutions to this apparent dichotomy have been attempted. They include the obvious one — speeding up microprocessors themselves. However, there’s a problem with that: Faster chips using electronics create more heat, generate interference and use more energy. All bad for data centers.

Using sound waves to speed up networks

Scientists say sound waves, though, could present a solution. They say one should convert the light zooming into the chip to sound — creating a kind of acoustic buffer (sound waves travel slower than light waves) — then process the data and turn it back into zippy light again, to be sent on its way.

Adding a “delay allows for the data to be briefly stored and managed inside the chip for processing, retrieval and further transmission as light waves,” explain scientists from University of Sydney in an article on the university’s website. The researchers say they’ve made a breakthrough. They say they have, for the first time, accomplished the world’s “first transfer of light to acoustic information on a chip.”

The chip-design advance could “speed up the Internet,” writes Christianna Silva in a Newsweek article.

Photonics, such as is used in fiber-optic cable, is better than traditional copper all around. For one thing, more bandwidth is supplied by photonics than by copper electronics.

That’s one reason why we use fiber, and it’s why chips are now being developed that, too, use photonics rather than copper.

“These chips are being developed for use in telecommunications, optical fiber networks and cloud computing data centers,” the university says.

Good and bad features of light as a data carrier

The article also says, “Light is an excellent carrier of information and is useful for taking data over long distances between continents through fiber-optic cables.” However, it can be a hindrance “when information is being processed in computers and telecommunication systems.”

The University of Sydney’s proposed chip concept, under development, will allow light to pass through the microprocessor in two to three nanoseconds, depending on engineering. Data can be stored on the chip for an additional 10 nanoseconds acoustically with the special chip, thus providing a moment for the number crunching.

“It is like the difference between thunder and lightning,” says Dr. Birgit Stiller, research fellow at the University of Sydney, of her five order-of-magnitude acoustic slowdown.

She means that it’s the same data or, in her thunderstorm analogy, the same energy, but it’s just traveling at different speeds depending on wavelength. As we know, a storm’s visual lightning flashes are experienced before the more lethargic, audible thunder clap in a thunderstorm. Same idea as with the chip.

“Once this technology is prepared to move into a commercial reality, computers will have all the benefits of data delivered by light-speed, beyond speed,” Silva wrote in her Newsweek article. “It would also be slow enough that today’s computer chips could actually read the information.”