The quantum process of atoms merging, and other previously unseen complex atomic interactions, have been observed by physicists for the first time. Until now, this was only understood through mathematics and statistical averaging from experiments involving large numbers of atoms.
Catching atoms in action as they unite to turn into a molecule requires a physicist to force the atoms to pause long enough for their exchanges to be recorded. The feat was achieved by the University of Otago researchers who “held” individual atoms in place by using a slew of equipment including laser tweezers (laser-based forceps), a vacuum chamber, mirrors, and microscopes assembled in Otago’s Department of Physics. It took a lot of expertise, time, and energy too. The research has been published in Physical Review Letters.
Mikkel F. Andersen, associate professor of Otago’s Department of Physics, said:
Our method involves the individual trapping and cooling of three 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. We slowly combine the traps containing the atoms to produce controlled interactions that we measure.
A microscopic camera was used to magnify and view the process of three atoms approaching each other. When that happens, two form a molecule, and the third maintains the bond while all three receive a kick from the energy discharged in the process.
Marvin Weyland, the postdoctoral researcher 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.
The results the researchers witnessed were different than what was expected from statistical averages because they were able to see the exact outcomes of individual processes. Weyland added:
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.
For instance, they watched a new process where two of the atoms left the experiment together – a level of detail impossible to observe in multi-atom experiments.
Andersen expects that the applications of this science will be useful in the development of future quantum technologies. Much like the ones that enabled modern computers and the Internet, which have impacted modern society tremendously.
Andersen said:
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.
Now the team will focus mainly on one experimental finding: why it took much longer than expected to form a molecule compared with other experiments and theoretical calculations. Of course, the theoretical predictions were not enough to explain this phenomenon, but the researchers believe they can use their new technique to help solve the discrepancy.
