Tiny storage
January 13, 2012
Researchers in Germany and the United States have built the smallest magnetic storage device in the world, signaling a potential breakthrough for computing.
In a paper published Thursday in the journal Science, researchers from the Institute of Applied Physics at the University of Hamburg in Germany and an IBM research lab in California demonstrated how they could store a bit, the smallest possible piece of digital information, in a set of 12 atoms.
Normally a bit, either a one or zero, would require about one million atoms in one of today's smallest silicon-based storage devices.
In the new technique, only two rows of six iron atoms on a surface of copper nitride were needed.
The researchers said it could be years before their technique leads to new consumer goods, but once perfected this method could lead to new types of nanomaterials able to store large amounts of information in tiny spaces, and to consume less energy while doing it.
"We have built up atom-by-atom data storage," said Andreas Heinrich, manager of the IBM laboratories in Almaden, California, in an interview with Deutsche Welle.
A new style of data storage
The new style of storing information turns a conventional magnetic hard drive on its head.
Instead of using normal ferromagnets made of iron, nickel or cobalt, the new method relies on antiferromagnets, which repel those same elements, granting them various magnetic orientations.
Traditionally, the ferromagnetic approach creates a magnetic field which limits how small a device can be shrunk.
But without the presence of this field, the sets of atoms can be configured in any way without such interference, explained Sebastian Loth, a physicist at the Max Planck Department for Structural Dynamics in Hamburg and a researcher at the IBM research lab in California.
"This new memory principle has the potential to revolutionize the computer technology," he said.
Larger size required for room temperature devices
The new result has already impressed other physicists.
"Current magnetic memory architectures are fundamentally limited in how small they can go," said Will Branford, a physicist at Imperial College London, in an interview with the BBC.
"This work shows that, in principle, data can be stored much more densely using antiferromagnetic bits."
However, the researchers note that this is just a very early step in creating smaller memory chips.
For the moment, this 12-atom array is only stable at a temperate of -268 degrees Celsius, near absolute zero. Loth said that at the moment the method would need a setup of about 150-200 atoms per bit of information to make it work at room temperature.
"It's as if we've opened a new door into the next room," Heinrich added.
Author: Judith Hartl / cjf
Editor: Andreas Sten-Ziemons / nw