Writers at the IEEE Spectrum report that molecule-size memory may be possible using graphene. Electrons flow extremely fast in graphene, much faster than in silicon, and a graphene transistor could really zip. That’s been the good news. The bad news, until now however, is that it’s hard to stop current from flowing in graphene once it starts. Reportedly, a group of researchers at AMO, a nanotechnology company in Germany, has come up with a novel mechanism for making a graphene switch. According to research published in the August issue of IEEE Electron Device Letters, the researchers found they could affect the conductance of graphene by using an electrical field.

When they switched the piece of graphene (we’re simplifying here – they created a three electorode, transistor-like sandwich of graphene and silicon dioxide) to its “off” state, it stayed that way. In other words, graphene could be used as nonvolatile memory. And, graphene can be produced in small units. “With graphene, we believe it can, in principle, be scaled down to a 1-nanometer-by-1-nanometer device,” says Max Lemme, one of the researchers and a Humboldt Research Fellow at the Center for Nanoscale Systems, at Harvard University. All this is obviously in its early stages. Currently, the switching speed is too slow for logic circuits and little is known about whether there is a limit to the memory cycles for this material. Engineering to manufacture memory using these materials is also years off.

At the molecular level, researchers are surprised by what they found bu think that what is going on is that a hydroxyl molecule is borrowed from the silicon dioxide and and sits on top of the graphene. “This is a controllable reaction,” says Andre Geim of the University of Manchester (U.K.). “You do not destroy the [graphene] backbone itself. You just detach and attach molecules and change the electrical properties.”