Quantum Computing Spins a Step Closer

Scientists at the University of California at Berkeley have made an important step towards the realization of quantum computing – a predicted technology that would use individual atoms as stand-ins for the transistor circuits on microchips.

The researchers have successfully measured the spin of an individual atom, or "adatom" – an atom sitting on top of another surface, rather than incorporated within it.

This is important in the process of turning atoms into components in nanocomputing devices. The theory behind quantum computing involves letting an atom's outermost electron function in the role of today's transistors, with the electron's "up" or "down" spin states representing the two alternating binary states of today's chip circuits.

Trouble is, scientists haven't been able to measure this spin well in the past, much less manipulate it. While practical use of the Berkeley technique remains far off, the observations and theory behind it are promising.

"From a technical point of view, this demonstrates a new ability to engineer, fabricate and measure spin-polarized nanostructures at the single atom level," said Michael F. Crommie, UC
Berkeley professor of physics. "Now that I can see an atom's spin, I can ask, 'What can I do with that atomic spin?' 'Can I manipulate it?'
'Can I use it, change it'?"

The team's report was published in the Physical Review Letters journal.

Physicists pin down atomic spin for spintronics [UC Berkeley Press Release]

(Image Credit: Michael Crommie/UC Berkeley)