Optical Computers Run At The Speed Of Light—Literally

Virtually every device you use—from the one you're using to read this to the pocket calculator growing dust in the back of your desk—relies on the same basic technology: circuits containing many tiny transistors that communicate with each other using electrons. We've come a very long way since the room-sized computers of the 1950s, but as computing gets smaller, faster, and more complicated, we get closer to hitting a wall. There's a physical limit to how powerful traditional computers can get. That's why scientists are turning to completely new forms of technology for future computers.

The first in our three-part series explored how some computers use artificial neurons to "think." Discover another way scientists are rethinking computing in the second part of the series below.

Computing At The Speed Of Light

Neurons are only one way to make computers more like brains. Another way is by changing the medium they use to communicate. Conventional computers exchange information in the form of electrons, while the human brain uses a complex mix of chemical signals. Some research suggests, however, that the brain also relies on light particles known as photons. What if computers did too?

Optical computing is designed to do just that. Photons can move information much more quickly than electrons can—they literally travel at the speed of light. We're already using photons to send data at breakneck speeds via fiber-optic cables; the problem is that the data has to be converted back into electrons once it arrives at its destination. If you could replace a computer's wires with optical waveguides, it might be able to do all the same things it could before at a much greater speed.

Photons Aren't A Fix-All

There are a few problems, though. For one thing, light waves are just too big for what we need them to do. According to ExtremeTech, "In general, the smallest useful wavelength of light for computing has been in the infrared range, around 1000 nm in size, while improvements in silicon transistors have seen them reach and even pass the 10 nm threshold." There are a few tricks scientists can use to get around this problem, but they add unnecessary complications to something that needs near-flawless speed and precision.

Still, the principles of optical computing are useful in certain circumstances. Li-Fi uses light instead of radiowaves to broadcast wireless internet 100 times faster than Wi-Fi, for instance. Technologies such as Optalsys have also found novel ways to get around light's limitations. In the future, your laptop may not run on photons, but optical computing will surely have a place.

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Watch And Learn: Our Favorite Content About Optical Computing

Researchers Create A Light-Based Microprocessor

It's up to 50 times faster than electron-based microprocessors.

Michio Kaku On The Computers Of The Future

What's beyond silicon chips?

Written by Ashley Hamer February 23, 2017
