In order to achieve levels of nanotechnology depicted in science fiction, we need to build machines one atom at a time. We're not there yet, but now we've got a powerful, indirect way to manipulate individual atoms.

Before this new breakthrough, the closest we had gotten to individual atom manipulation was to rather clumsily push atoms around using a scanning tunnelling microscope, or STM. This microscope has a stylus that is only one atom thick, from which it shoots electrons to obtain images on the atomic scale. Although this method did allow direct control of individual atoms, it was a rough, inefficient process that didn't offer much hope of acquiring the precision necessary for nanotechnology.


That may be about to change, thanks to Richard Palmer, Peter Sloan, and Sumet Sakulsermsuk of the UK's University of Birmingham. They placed the stylus of an STM in a tiny indent on a thin slice of silicon, and then emitted electrons from the stylus. The electrons burrowed into the silicons and traveled like a quantum wave function. This allowed them to avoid surface imperfections that would otherwise obstruct their path. The researchers have dubbed this electron wave a "quantum submarine."

Now, here's the important part as far as nanotechnology is concerned. The electrons broke the chemical bonds holding chlorobenzene molecules to the surface of the silicon crystal. With those molecules dispatched, it's now possible to manipulate the atoms on the silicon surface. The researchers suggest one could manufacture silicon wafers using just this method, in which tiny pits are created on the surface into which electrons can be injected.


The resulting electron waves would then shape and pattern the surface according to the placement and power of the wave, allowing precise manipulation of the silicon's individual atoms, which would be a huge step towards eventually achieving the nanotechnology of science fiction.

[Physics Review Letters via The New Scientist]