Work

Rotational excitation in sympathetic cooling of diatomic molecular ions by laser-cooled atomic ions

Year: 2026

Type: article

Abstract: Sympathetic cooling of molecular ions through the Coulomb interaction with laser-cooled atomic ions is an efficient tool to prepare translationally cold molecules without, ideally, affecting the internal state of the molecular ions. However, the electric field due to the Coulomb interaction may induce rotational transitions that change the purity of initially quantum state prepared molecules. Here, we use estimates of rotational state changes in single collisions of diatomic ions with atomic ions [J. M. Berglund, M. Drewsen, and C. P. Koch, ] to determine the overall rotational excitation accumulated over the sympathetic cooling. Considering two different experimental scenarios, that of a molecular ion cotrapped with a single atomic ion and a molecular ion immersed in a Coulomb crystal of atomic ions, we also estimate the cooling time.

Source: Physical Review A

DOI: 10.1103/7kym-lfxl

Authors: J. Martin Berglund, Michael Drewsen, Christiane P. Koch

Institutions: University of Kassel, Autonomous University of San Luis Potosí, Aarhus University, Freie Universität Berlin

Language: English

Topic: Cold Atom Physics and Bose-Einstein Condensates

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,675

Funders: National Science Foundation, Villum Fonden, European Commission, Danmarks Frie Forskningsfond