• DOI:10.1038/s41586-021-04112-y
• Corpus ID: 234789967

Observation of Feshbach resonances between a single ion and ultracold atoms

@article{Weckesser2021ObservationOF,
  title={Observation of Feshbach resonances between a single ion and ultracold atoms},
  author={Pascal Weckesser and Fabian Thielemann and Dariusz Wiater and Agata Wojciechowska and Leon Karpa and Krzysztof Jachymski and Michał Tomza and Thomas Walker and Tobias Schaetz},
  journal={Nature},
  year={2021},
  volume={600},
  pages={429 - 433}
}

• P. Weckesser, F. Thielemann, +6 authors T. Schaetz
• Published 19 May 2021
• Physics
• Nature

The control of physical systems and their dynamics on the level of individual quanta underpins both fundamental science and quantum technologies. Trapped atomic and molecular systems, neutral1 and charged2, are at the forefront of quantum science. Their extraordinary level of control is evidenced by numerous applications in quantum information processing3,4 and quantum metrology5,6. Studies of the long-range interactions between these systems when combined in a hybrid atom–ion trap7,8 have led to landmark results9–19. However, reaching the ultracold regime—where quantum mechanics dominates the interaction, for example, giving access to controllable scattering resonances20,21—has so far been elusive. Here we demonstrate Feshbach resonances between ions and atoms, using magnetically tunable interactions between 138Ba+ ions and 6Li atoms. We tune the experimental parameters to probe different interaction processes—first, enhancing three-body reactions22,23 and the related losses to identify the resonances and then making two-body interactions dominant to investigate the ion’s sympathetic cooling19 in the ultracold atomic bath. Our results provide deeper insights into atom–ion interactions, giving access to complex many-body systems24–27 and applications in experimental quantum simulation28–30. Magnetically tunable interactions between lithium atoms and barium ions are used to demonstrate and probe Feshbach resonances between atoms and ions, which could have applications in the fields of experimental quantum simulation and fundamental physics.