A diamond is forever. And in a few years, you could say the same about everything you say on Twitter. Researchers from the University of California at Berkeley have found a way to develop a carbon nanotube-based technique for storing data that could potentially last more than a billion years.
The goal, say the researchers, is to improve on what they see as the general trend for memory storage. As memory density increases, the lifespan of the storage has been decreasing, they say. For instance, stone carvings are still largely readable after 3,800 years, while information written with individual atoms by scanning tunneling microscopes last just a few seconds at room temperature. Conventional digital memory technologies in use — such as hard disk drives and flash memory — have an estimated lifetime of only 10 to 30 years. If successful, a billion-year memory storage device could change that, enabling humans to store any data — from the digital version of an ancient manuscript to your latest tweet — from now until long after the Earth has been overrun by superintelligent, fusion-powered cyborg ants.
Here’s how it works. The device has an iron nanoparticle positioned inside a hollow carbon nanotube. Carbon nanotubes are molecular-scale tubes usually made of a carbon allotrope. For data storage, a small electrical signal is applied across the nanotube causing the iron nanoparticle shuttle to move back and forth. The movement of the nanoparticles from one end to the other of the tube creates the binary ‘1′ or ‘0′ state.
The position of the shuttle can be read out directly, explain the researchers in a paper published in the current issue of the Nano Letters journal. “The reversibility of the nanoparticle motion allows a memory bit that can be rewritten,” according to the paper.
The technique has significant potential for archival storage, say the researchers, because the nanoparticle-based bits show significant persistence. It’s also possible to store a lot of data in a small space: With information density predicted to be as high as 1012 bits per square inch, you could store data from nearly 25 DVDs in the space of a postage stamp.
The beauty of the system is that it requires only a couple volts of electrical signal to stimulate it, Will Gannett, a graduate student in physics working on the project at UC Berkeley told campus paper The Daily Californian.
It’ll take awhile to get there, though — so far the researchers have only demonstrated the theoretical possibility of this technology.
[via Science]
Photo: Nanoparticle in nanotube representation
