The boffins at Big Blue have offered another of their tantalising glimpses into the future of computing with the announcement of two major feats in the field of nanotechnology that could one day lead to new kinds of devices and structures built from a few atoms or molecules.

In the latest edition of the journal Science, IBM scientists describe major progress in probing a property called magnetic anisotropy in individual atoms. This measurement has important technological consequences because it determines an atom’s ability to store information. Previously, nobody had been able to measure the magnetic anisotropy of a single atom.

IBM says that with further work it may be possible to build structures consisting of small clusters of atoms, or even individual atoms, that could reliably store magnetic information. It claims that such a storage capability would enable nearly 30,000 feature length films or the entire contents of YouTube -- millions of videos estimated to be more than 1,000 trillion bits of data -- to fit in a device the size of an iPod. Perhaps more importantly, the breakthrough could lead to new kinds of structures and devices that are so small they could be applied to entire new fields and disciplines beyond traditional computing.

In a second report for Science, IBM researchers unveiled the first single-molecule switch that can operate flawlessly without disrupting the molecule's outer frame -- a significant step toward building computing elements at the molecular scale that are vastly smaller, faster and use less energy than today's computer chips and memory devices. In addition to switching within a single molecule, the researchers also demonstrated that atoms inside one molecule can be used to switch atoms in an adjacent molecule, representing a rudimentary logic element. This is made possible partly because the molecular framework is not disturbed.

IBM researchers describe the ability to switch a single molecule “on” and “off,” a basic element of computer logic, using two hydrogen atoms within a naphthalocyanine organic molecule. Previously, researchers at IBM and elsewhere have demonstrated switching within single molecules, but the molecules would change their shape when switching, making them unsuitable for building logic gates for computer chips or memory elements.

Switches inside computer chips act like a light switch to turn the flow of electrons on and off and, when put together, make up the logic gates, which in turn make up electrical circuits. Having ever smaller switches allows the circuits to be shrunk to ever smaller sizes, making it possible to pack more circuits into a processor and boosting speed and performance.

To that end, IBM says that molecular switches could one day lead to computer chips with speeds as fast as today's fastest supercomputers, but much smaller in size; with some speculating even building computer chips so small they could be the size of a speck of dust or fit on the tip of a needle.

Development of conventional silicon-based CMOS chips is approaching its physical limits so a new technology is needed. Modular molecular logic is a possible candidate, though still several years from reality. The next step for the IBM’s research team is to build a series of these molecules into a circuit, then figure out how to network those together into a molecular chip.

Seamus Quinn