Collision resonances between ultracold atom and molecules visualized for the first time

January 23, 2019, University of Science and Technology of China
Illustration of Magnetically tunable Feshbach resonances in ultracold atom-molecule collisions. Credit: Jian-wei Pan's team

For the first time, a team led by Prof. Jian-Wei Pan and Prof. Bo Zhao at the University of Science and Technology of China, have successfully observed scattering resonances between atoms and molecules at ultra-low temperatures, shedding light on the quantum nature of atom-molecule interactions that have so far only been discussed in theory. These observations greatly aid in the advancement of ultra-cold polar molecules and ultra-cold chemical physics. The new insights inform several other disciplines, such as designing high precision clocks, powerful microscopes, biological compasses and super-powerful quantum computers.

The field of chemical physics, a subcategory of quantum chemistry, has long been focusing on understanding the interactions of atoms and molecules at their very basic levels. Specifically, the aim has been to elucidate the scattering resonances, a remarkable quantum phenomenon that is expected to be a routine rather than an exception at temperatures near absolute zero. Specific to this research, the focus has been an understanding of scattering resonances of heavy molecules at ultra-cold temperatures, conditions under which particles move so slowly that one has enough time to both investigate and control their structure and motion with either electric or magnetic fields.

The first-of-its-kind study is published in the journal Science this week. It describes a specific type of interaction between atoms and molecules, namely potassium-40 (40K) atoms and sodium-23-potassium-40 (23Na40K) molecules. This interaction was taking place at and was manipulated by a magnetic field. The authors were thereby able to observe the specific scattering resonances, between the aforementioned atoms and molecules, which was so far only theorized.

"The molecules are heavy, and the structure of their energy field is very complex, which may result in a large amount of atom-molecule resonances," according to Bo Zhao. "Theory cannot predict the positions of these atom-molecule resonances. In fact, it is unclear whether the atom-molecule resonances at ultra-cold temperatures are resolvable and observable prior to our work," he adds.

The news findings offer knowledge that can be applied to better understand other atom-molecule interactions. The USTC team has devised a tool that can accurately monitor particle behavior so that a plethora of other interactions and dynamics can be visualized rather than theorized.

In their future endeavors, the team aims to explore even more parameters in order to understand them. "The next step is to measure more resonances and try to understand them. Our hope is to collaborate with theoreticians and find an accurate and predictive model that can understand and predict the atom-molecule scattering at ultra-low temperatures. This is the ultimate gold of studying ultra-cold collisions involving ," according to Zhao.

Explore further: Quantum LEGO—building ultracold molecules

More information: Huan Yang et al, Observation of magnetically tunable Feshbach resonances in ultracold 23Na40K + 40K collisions, Science (2019). DOI: 10.1126/science.aau5322

Related Stories

Quantum LEGO—building ultracold molecules

June 12, 2018

Cooling matter is not easy. Atoms and molecules have the tendency to jump around, to rotate and to vibrate. Freezing these particles by slowing them down is a complicated process. For individual atoms, physicists have figured ...

Laser cooling a polyatomic molecule

April 26, 2017

(Phys.org)—A team of researchers at Harvard University has successfully cooled a three-atom molecule down to near absolute zero for the first time. In their paper published in Physical Review Letters, the team describes ...

Recommended for you

CMS gets first result using largest-ever LHC data sample

February 15, 2019

Just under three months after the final proton–proton collisions from the Large Hadron Collider (LHC)'s second run (Run 2), the CMS collaboration has submitted its first paper based on the full LHC dataset collected in ...

Gravitational waves will settle cosmic conundrum

February 14, 2019

Measurements of gravitational waves from approximately 50 binary neutron stars over the next decade will definitively resolve an intense debate about how quickly our universe is expanding, according to findings from an international ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.