Molecular Photoassociation and Ultracold Molecules

Olivier Dulieu, Jesús Pérez‐Ríos, Maxence Lepers

Edward E. Eyler, William C. Stwalley, P. L. Gould

Jesús Pérez‐Ríos, May E. Kim, Chen-Lung Hung

Photoassociation (PA) is a powerful technique to synthesize molecules directly and continuously from cold and ultracold atoms into deeply bound molecular states.In freespace, however, PA efficiency is constrained by the number of spontaneous decay channels linking the initial excited molecular state to a sea of final (meta)stable rovibronic levels.Here, we propose a novel scheme based on molecules strongly coupled to a guided photonic mode in a photonic crystal waveguide that turns PA into a powerful tool for near deterministic formation of ultracold molecules in their ground rovibrational level.Our example shows a potential ground state molecule production efficiency 90% > , and a saturation rate 10 6 > molecules per second.By combining state-of-the-art cold atomic and molecular physics with nanophotonic engineering, our scheme presents a novel experimental package for trapping, cooling, and optically manipulating ultracold molecules, thus opening up new possibilities in the direction of ultracold chemistry and quantum information.

Philippe Pellegrini, Marko Gacesa, Robin Côté

Ultracold molecules offer a broad variety of applications, ranging from metrology to quantum computing. However, forming "real" ultracold molecules, i.e., in deeply bound levels, is a very difficult proposition. Here, we show how photoassociation in the vicinity of a Feshbach resonance enhances molecular formation rates by several orders of magnitude. We illustrate this effect in heteronuclear systems, and find giant rate coefficients even in deeply bound levels. We also give a simple analytical expression for the photoassociation rate and discuss future applications of the Feshbach-optimized photoassociation technique.

Daniel J. Heinzen, Joseph D. Miller, Robert A. Cline

Randall G. Hulet