The scientists have developed the world’s first computer which is built entirely with carbon nanotubes. The invention has opened the door to a new generation of faster-running digital devices.
Carbon nanotubes – a semiconductor material – has the potential to launch a new generation of electronic devices that run faster and uses less energy than those made from silicon chips, according to the researchers. Carbon nanotubes, also called CNTs, are long chains of carbon atoms that are extremely efficient at conducting and controlling electricity. They are so thin that thousands of CNTs could fit side by side in a human hair. Due to the thinness, they take very little energy to switch them off, according to Wong, a co-author of the paper.
“People have been talking about a new era of carbon nanotube electronics moving beyond silicon. But there have been few demonstrations of complete digital systems using this exciting technology. Here is the proof,” said Subhasish Mitra, an electrical engineer and computer scientist at Stanford University who is also the lead author of the study.
The Stanford researchers created a powerful algorithm that maps out a circuit layout that is guaranteed to work no matter whether or where CNTs might be askew.
“This ‘imperfections-immune design’ (technique) makes this discovery truly exemplary,” said Sankar Basu, a programme director at the National Science Foundation.
Researchers used this imperfection-immune design to assemble a basic computer with 178 transistors, a limit imposed by the fact that they used the university’s chip-making facilities rather than an industrial fabrication process.
Their CNT computer performed tasks such as counting and number sorting. It runs a basic operating system that allows it to swap between these processes.
The study was published in the journal Nature.
1 bit processor
Speed: 1 kHz
10-200 nanotubes per transistor
2 billion carbon atoms
How small is a carbon computer chip?
100 microns – width of human hair
10 microns – water droplet
8 microns – transistors in Cedric
625 nanometres (nm) – wavelength of red light
20-450 nm – single viruses
22 nm latest silicon chips
9 nm – smallest carbon nanotube chip
6 nm – cell membrane
1 nm – single carbon nanotube