Chemists design a molecule using optical tweezers

spinonews optical tweezers

Optical tweezers

Scientists design a molecule using optical tweezers and spearheading an entirely new form of chemical reaction. In the study, a team of Harvard researchers trapped two individual atoms in separate laser beams, then united them together and triggered a reaction between them with a photon of light.

Lee Liu, the lead author, said, we are putting atoms together more like Lego, rather than mixing chemicals and relying on chance collisions. We are doing chemistry in a way that is totally new and surprising.

Current chemical synthesis methods

Current chemical synthesis methods typically involve often toxic solvents. But, the Harvard team’s technique, which triggers the reaction with a very specific pulse of light that binds the two atoms, allows very precise control.

The team built up the method in their mission for new qubits. The molecules interact strongly with different atoms, which is critical for quantum preparing. They also have a more complex cluster of energy levels available for storing quantum data.

optical tweezers
Source: Harvard

While the combination of interactions and storage make the molecules more encouraging than many existing qubits that depend on single atoms. The major drawback of molecules is difficult to cool to the extremely low temperatures required for controlling quantum interactions.

Liu and the team avoided this problem by using cold atoms to build a molecule that was already cold.

They cooled and trapped an atom of cesium in a strongly focused laser beam, known as optical tweezers. In another laser beam they trapped a cold sodium atom and moved the two together into a single optical tweezers.

There, the large cesium and the diminutive sodium atoms waited until the scientists injected a pulse of light with the requisite energy to bind the pair into a sodium cesium molecule, a process called photoassociation.

Even though the reaction was effective, the resultant sodium cesium molecule initially in too excited state of quantum computing. However, the researchers investigating strategies to chill it down to its ground state with another laser.

After their own quantum computing experiments, the technique opens a new way to explore the quantum mechanics of chemical reactions.