arXiv:1612.03533 · Physical Review A
Zeeman-insensitive cooling of a single atom to its two-dimensional motional ground state in tightly focused optical tweezers
Pimonpan Sompet, Y. H. Fung, Eyal Schwartz, Matthew D. J. Hunter, J. Phrompao, Mikkel F. Andersen
Abstract
We combine near-deterministic preparation of a single atom with Raman sideband cooling, to create a push-button mechanism to prepare a single atom in the motional ground state of tightly focused optical tweezers. In the two-dimensional (2D) radial plane, we achieve a large ground-state fidelity for the entire procedure (loading and cooling) of $\ensuremath{\sim}0.73$, while the ground-state occupancy is $\ensuremath{\sim}0.88$ for realizations with a single atom present. For 1D axial cooling, we attain a ground-state fraction of $\ensuremath{\sim}0.52$. The combined 3D cooling provides a ground-state population of $\ensuremath{\sim}0.11$. Our Raman sideband cooling variation is indifferent to magnetic field fluctuations, allowing widespread unshielded experimental implementations. Our work provides a pathway towards a range of coherent few-body experiments.