Building Single Molecules – reactions, collisions, and spectroscopy of two atoms
Kang-Kuen Ni, Assistant Professor of Chemistry and Chemical Biology, Harvard University
Ultracold polar molecules are sought-after for a range of new possibilities from studying ultracold chemical reactions to building quantum simulators and computers. My group develops physics techniques to build single ultracold molecules atom-by-atom. This work allows us to go beyond the usual paradigm of chemical reactions that proceed via stochastic encounters between reactants, to a single, controlled reaction of exactly two atoms [1, 2]. We foresee single molecules as valuable resources for quantum simulation and quantum computation  due to their rich internal degrees of freedom and strong tunable inter-molecular coupling.
 L. R. Liu, J. D. Hood, Y. Yu, J. T. Zhang, N. R. Hutzler, T. Rosenband, K.-K. Ni. Building one molecule from a reservoir of two atoms. Science 360, 900 (2018);
 L. R. Liu, J. D. Hood, Y. Yu, J. T. Zhang, K. Wang, Y.-W. Lin, T. Rosenband, and K.-K. Ni. Ground State Cooling and Transport of Single Atoms for Ultracold Molecular Assembly. arXiv:1902.03935 (2019)
 K.-K. Ni, T. Rosenband, D. D. Grimes. Dipolar exchange quantum logic gate with polar molecules. Chemical Science 9, 6830 (2018)