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  • Open Access

Modeling optical formation of ultracold NaK2 ground-state molecules

Baraa Shammout1,*, Leon Karpa1, Silke Ospelkaus1, Eberhard Tiemann1, and Olivier Dulieu2,†

  • *Contact author: shammout@iqo.uni-hannover.de
  • †Contact author: olivier.dulieu@universite-paris-saclay.fr
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Phys. Rev. Research 8, 013030 – Published 14 January, 2026

DOI: https://doi.org/10.1103/y7gm-1w9c

Abstract

We study the rovibronic transitions in NaK2 between its electronic ground state 12A′ and its second excited state 32A′, to identify possible pathways for the creation of ultracold ground-state triatomic molecules. Our methodology relies on the computation of potential energy surfaces and transition dipole moment surfaces for the relevant electronic states using ab initio methods. Rovibrational energy levels and wave functions are determined using the discrete variable representation approach. A double-well structure of the potential energy surface is identified for both states, and the related transition strengths between the rovibrational levels are derived. Our calculations show that the formation of ultracold ground-state NaK2 molecules is expected when starting from an excited electronic state of NaK2, which can be created by photoassociation of NaK and K, as observed by optical means by Cao, et al. [Phys. Rev. Lett. 132, 093403 (2024)].

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Phys. Rev. Research 8, 013030– Published 14 January, 2026
  • Received 22 August 2025
  • Accepted 20 November 2025
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