Recent decades have seen great interest in novel carbon structures such as buckyballs and nanotubes. In 1997 researchers in Australia discovered yet another form of carbon: a spidery, fractallike composition they dubbed nanofoam. At this year's March meeting of the American Physical Society, the group reported that this gossamer substance is ferromagnetic (like iron), the only type of pure carbon that has that property. The foam's magnetic behavior suggests that innovative uses might be possible, such as serving as a contrast-enhancing agent in magnetic resonance imaging.
Andrei V. Rode and his co-workers at the Australian National University in Canberra created carbon nanofoam when they blasted a glassy form of carbon with a series of short laser pulses in a container filled with inert argon gas. The pulses produced a plume of carbon vapor that settled as a thin layer on the vessel walls. To the naked eye, it looks like a conventional soot deposit.
This article was originally published with the title Magnetic Soot.