Scientists held individual atoms in place

First bottom-up assembly of atom triads.

For the first time in quantum physics, scientists from the University of Otago became successful in holding the individual atoms in place. They also observed previously unseen complex atomic interactions. The experiment offers a previously unseen view into the microscopic world, surprising researchers with the results.

Until now, this quantum process was only understood through statistical averaging from experiments involving large numbers of atoms.

Scientists trapped and cooled three individual atoms to a temperature of about a millionth of a Kelvin using highly focused laser beams in a hyper-evacuated (vacuum) chamber, around the size of a toaster. They then slowly combined the traps containing the atoms to produce controlled interactions that we measure.

When the three particles approach one another, two forms a molecule, and all get a kick from the energy discharged in the process. A microscope camera permits the procedure to be magnified and viewed.

Postdoctoral Researcher Marvin Weyland, who spearheaded the experiment, said“Two atoms alone can’t form a molecule, it takes at least three to do chemistry. Our work is the first time this basic process has been studied in isolation, and it turns out that it gave several surprising results that were not expected from the previous measurement in large clouds of atoms.”

“By working at this molecular level, we now know more about how atoms collide and react with one another. With development, this technique could provide a way to build and control single molecules of particular chemicals.”

Associate Professor Andersen admits the technique and level of detail can be difficult to comprehend to those outside the world of quantum physics. However, he believes the applications of this science will be useful in the development of future quantum technologies that might impact society as much as earlier quantum technologies that enabled modern computers and the Internet.

“Research on being able to build on a smaller and smaller scale has powered much of the technological development over the past decades. For example, it is the sole reason that today’s cellphones have more computing power than the supercomputers of the 1980s. Our research tries to pave the way for being able to build at the very smallest scale possible, namely the atomic scale, and I am thrilled to see how our discoveries will influence technological advancements in the future,” Associate Professor Andersen says.

The experiment findings showed that it took much longer than expected to form a molecule compared with other experiments and theoretical calculations, which currently are insufficient to explain this phenomenon. While the researchers suggest mechanisms that may explain the discrepancy, they highlight a need for further theoretical developments in this area of experimental quantum mechanics.

The study is published in the journal Physical Review Letters.

See stories of the future in your inbox every morning.