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Spectroscopy and Ground-State Transfer of Ultracold Bosonic  K39133Cs Molecules

Krzysztof P. Zamarski*, Charly Beulenkamp*, Yi Zeng, Manuele Landini, and Hanns-Christoph Nägerl†

  • Universität Innsbruck, Institut für Experimentalphysik und Zentrum für Quantenphysik, Technikerstraße 25, 6020 Innsbruck, Austria

  • *These authors contributed equally to this work.
  • †Contact author: christoph.naegerl@uibk.ac.at
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Phys. Rev. Lett. 135, 203401 – Published 12 November, 2025Erratum Phys. Rev. Lett. 136, 249902 (2026)

DOI: https://doi.org/10.1103/gjzh-8dsb

Abstract

We report the creation of ultracold samples of  K39133Cs molecules in their rovibrational ground state. By investigating potentially suitable excited states using one- and two-photon spectroscopy, we have identified a pathway to the ground state via an exceptionally narrow intermediate state. Using stimulated Raman adiabatic passage, we create trapped samples of up to 3500 molecules at temperatures of 1  μK with one-way efficiencies of 71%. The lifetime of these samples is limited by a near-universal two-body loss process, which could shed new light on similar loss mechanisms in other molecular species. Our results are a step toward establishing an alternative molecular species as a platform for the study of bosonic and fermionic quantum matter with strong dipolar interactions.

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Erratum

Erratum: Spectroscopy and Ground-State Transfer of Ultracold Bosonic K39Cs133 Molecules [Phys. Rev. Lett. 135, 203401 (2025)]

Krzysztof P. Zamarski, Charly Beulenkamp, Yi Zeng, Manuele Landini, and Hanns-Christoph Nägerl
Phys. Rev. Lett. 136, 249902 (2026)

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Phys. Rev. Lett. 135, 203401– Published 12 November, 2025
  • Received 12 June 2025
  • Accepted 16 September 2025
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