Abstract
We report coherent association of atoms into a single weakly bound NaCs molecule in an optical tweezer through an optical Raman transition. The Raman technique uses a deeply bound electronic excited intermediate state to achieve a large transition dipole moment while reducing photon scattering. Starting from two atoms in their relative motional ground state, we achieve an optical transfer efficiency of 69%. The molecules have a binding energy of 770.2 MHz at 8.83(2) G. This technique does not rely on Feshbach resonances or narrow excited-state lines and may allow a wide range of molecular species to be assembled atom by atom.
1 More- Received 17 December 2020
- Revised 11 May 2021
- Accepted 12 July 2021
DOI:https://doi.org/10.1103/PhysRevX.11.031061
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Published by the American Physical Society
Physics Subject Headings (PhySH)
Popular Summary
Systems built from ultracold molecules are promising for many applications such as precision measurements and quantum information thanks to their rich internal states and strong interactions. For most molecular species, however, full control of such inherent complexity remains challenging. Currently, the most successful approach relies heavily on special properties of the system. Here, we experimentally demonstrate a more general approach: using optical transitions to pair a sodium and a cesium atom in the same optical tweezer to form a NaCs molecule.
We achieve full control of the molecule we create by first fully controlling the constituent atoms and then mapping this control to molecules through association. This approach must overcome the large size mismatch between the initial free-atom state and the final molecular bound state through careful selection of all the states involved. We demonstrate the coherence of this mapping by driving the atom pair back and forth to its weakly bound state.
Compared to the most reliable approach to date, which uses magnetic Feshbach resonances, our method uses only optical transitions that are abundant for pairs of atoms and could allow a diverse range of molecules to be associated atom by atom. The molecules we create can be transferred to other states, with stronger interactions to be used for quantum computation and simulation.