Boffins one step closer to solving nanoscale computer challenge
Design could nail Feynman Grand Challenge
Scientists at the University of California, Santa Barbara have developed a design of a working nanoscale computing device that could complete the Feynman Grand Challenge.
Richard Feynman’s famous talk “Plenty of Room at the Bottom” is considered a precursor to the boom in nanotechnology. Although there has been much progress in the miniaturization of technology, no team has ever won the Feynman Grand Challenge, a competition set by the Foresight Institute.
The goal is to build an eight-bit digital computer circuit capable of adding two numbers in 50nm by 50nm – the size of a biological virus.
Although no one has ever completed the challenge, the nanoscale computing circuit design “presents a viable solution,” the researchers claim. The design is published in Nano Research and works by using a logic system called material implication logic with memristors.
Memristors work by having a changing electrical resistance dependent on the amount of current flowed through the device previously. It logs the current levels and keeps it in its history, essentially.
This saves precious space, as logic operation and information storage can happen simultaneously, so fewer components are needed. The memristor stores the computation in its memory and can be retrieved after the device is turned off.
“In a regular computer, data processing and memory storage are separated, which slows down computation. Processing data directly inside a three-dimensional memory structure would allow more data to be stored and processed much faster,” said Gina Adam, lead author and postdoctoral researcher at UCSB’s Department of Electrical and Computer Engineering.
The key to solving the Feynman Grand Challenge is that the two-dimensional circuit can be stacked to create a three-dimensional device within 50-by-50 nanometres.
But there is a big obstacle standing in the team’s way. Memristors are still being heavily researched and are not commercially available yet.
“Since this technology is still new, more research is needed to increase its reliability and lifetime and to demonstrate large scale three-dimensional circuits tightly packed in tens or hundreds of layers,” Adam said. ®