Cool Discoveries with Ultracold Molecules—Literally
Ultracold molecules open door to discovering new states of matter
Dr. David Chandler
When chilled to temperatures below one degree kelvin, just above the coldest temperature possible, molecules behave differently, explained Dr. David Chandler in his talk "The Quest for Ultracold Molecules" at the recent Pacific Northwest National Laboratory Frontiers in Chemical Physics & Analysis. The series features leaders from industry, government, and academia that discuss novel ideas and advancements in science.
Dr. Chandler discussed the cooling of molecules to ultracold temperatures, where the quantum nature of the gas dominate their interactions. Cooling atoms and molecules has resulted in discoveries, such as the realization and study of new states of matter.
In addition to forming new states of matter, cooling atoms to millikelvin temperatures, and below, has enabled ultra-high resolution spectroscopy studies and the extraction of information about the collisional dynamics of atoms and their interactions. The wave-like nature of ultracold molecules is also predicted to lead to a new understanding of weak interactions between molecules and novel technologies such as quantum computers.
Creating ultracold molecules: The field of ultracold molecule studies had remained generally unexplored due to the complexity of making ultracold samples. However, Dr. Chandler and his colleagues developed an approach to chilling molecules. The approach is called kinematic cooling.
With kinematic cooling, Chandler and his colleagues have produced measurable amounts of ultracold molecules with temperatures ranging from 10-100 mK. They created the molecules using a unique molecular beam scattering technique. The cold molecules are formed at the intersection of an atomic beam and a molecular beam. The collisions between the beams remove the translational motion from a molecule, thereby cooling it. With this technique, Chandler and his team have demonstrated the ability to produce cold molecules that can be observed for 100s of microseconds, opening the door to further studies.
About Dr. Chandler: Dr. Chandler became a staff scientist at Sandia National Laboratories in 1982 where he pursued his interest in photochemistry of small molecules. In collaboration with Dr. Paul Houston (Cornell University), he developed the technique of Ion Imaging for which he was elected Fellow of American Physical Society. His use of the technique to study both unimolecular dissociation and bimolecular scattering led to his discovery of kinematic cooling.