First Light-based 'Metatronic' Circuit Created
"Looking at the success of electronics over the last century, I have always wondered why we should be limited to electric current in making circuits. If we moved to shorter wavelengths in the electromagnetic spectrum -- like light -- we could make things smaller, faster and more efficient,"Said Nader Engheta, professor in the electrical and systems engineering department of Penn's School of Engineering and Applied Science.
He is working on making that dream a reality. He and his team have successfully managed to make the world’s first “lumped” optical circuit. Lumping, in the world of electronics, means that the element can be treated discretely, that it is its own element, just like other elements like NAND gates, etc. An engineer doesn’t need to know how a lumped circuit was put together to use it; he just uses it. And Engheta’s success opens up a world of possibilities.
Fiber optic cables have proven to be much, much better than their metal counterparts at carrying large amounts of data. But the light beams can’t travel indefinitely with the data. Every once in a while, you need a circuit that will receive the data and retransmit it. Right now, that circuit is silicon and metal, and it slows the circuit down. The translation time from light to the circuit takes time, and it slows the circuit down.
Optical circuits don’t have nearly the latency problems that regular circuits do, so what you get is a faster circuit, as well as a more robust design. This applies to many other common circuits, too, like computer processors, if the circuits can be made small enough.
The team has managed to design 3 different basic circuit types that can be used to build pretty much any type of logic gate, the fundamental building blocks of computers. And while the designs are efficient, the team bets they can make them even greater by building them in 3D, rather than flat, as they are doing now.
So, if Engheta gets his way, we may soon have computers that work at the speed of light.