State-to-state chemistry for three-body recombination in an ultracold rubidium gas

• Published in: Science (American Association for the Advancement of Science) Vol. 358; no. 6365; pp. 921 - 924
• Main Authors: Wolf, Joschka, Deiß, Markus, Krükow, Artjom, Tiemann, Eberhard, Ruzic, Brandon P., Wang, Yujun, D’Incao, José P., Julienne, Paul S., Denschlag, ohannes Hecker
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 17.11.2017; The American Association for the Advancement of Science
• Subjects: Atomic properties; Beams (radiation); Chemical reactions; Collision dynamics; Molecular beams; Organic Chemistry; Quantum mechanics; Quantum theory; Recombination; Rubidium; Splitting
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aan8721

Experimental investigation of chemical reactions with full quantum state resolution for all reactants and products has been a long-term challenge. Here we prepare an ultracold few-body quantum state of reactants and demonstrate state-to-state chemistry for the recombination of three spin-polarized ultracold rubidium (Rb) atoms to form a weakly bound Rb₂ molecule. The measured product distribution covers about 90% of the final products, and we are able to discriminate between product states with a level splitting as small as 20 megahertz multiplied by Planck’s constant. Furthermore, we formulate propensity rules for the distribution of products, and we develop a theoretical model that predicts many of our experimental observations. The scheme can readily be adapted to other species and opens a door to detailed investigations of inelastic or reactive processes.