Cooling, trapping, and controlling molecular gases at subKevin temperatures is a new research frontier at the interface of chemistry and physics. We develop quantum scattering theories and perform accurate numerical calculations of atomic and molecular collisions at ultralow temperatures and explore novel ways to control chemical reactivity with external electromagnetic fields.
The research field of cold molecules encompasses several quickly developing research frontiers made possible by the groundbreaking experimental advances in the production of cold molecular gases chilled to temperatures below 1 K. At low temperatures, molecules acquire new, strange, and unexpected properties as quantum mechanical effects (such as tunneling and particle statistics) begin to influence their behavior. A hallmark of ultracold chemical dynamics is the ability to control chemical reactivity with external electromagnetic fields. Since quantum mechanical effects play a key role in molecular collisions and chemical reactions at ultralow temperatures, it is essential to properly include these effects in theoretical simulations of these few-body processes. We develop efficient theoretical algorithms for solving quantum molecular scattering problems in the presence of external electromagnetic fields. This methodology is put to use in large-scale numerical simulations of atom-molecule and molecule-molecule collision dynamics, including chemical reactions in ultracold molecular ensembles.