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arXiv · 2504.00590

A linear rotor trapped and coupled to the vibrational modes of an ion crystal

Monika Leibscher·Juan M. Garcia-Garrido·Konstantin Gaul·Rosario Gonzalez-Ferez·Ferdinand Schmidt-Kaler·Christiane P. Koch
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Abstract

When molecular ions are trapped together with atomic ions in a Paul trap, their dipole moment couples the molecular rotation to the joint vibrational motion of the particles in the trap. To leverage this coupling for quantum control, a rotational transition in the molecule should be resonant with one of the ion crystal vibrational modes. Focusing on the example of singly charged thorium fluoride molecular ions, cotrapped with two ytterbium ions, we determine the conditions for resonant dipole-phonon coupling, fully accounting for the molecular hyperfine structure. We identify several choices for resonant coupling and discuss its detection using sideband-resolved laser spectroscopy and measurements of decoherence.

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Monika Leibscher, Juan M. Garcia-Garrido, Konstantin Gaul, Rosario Gonzalez-Ferez, Ferdinand Schmidt-Kaler, Christiane P. Koch. 2025-04-01. A linear rotor trapped and coupled to the vibrational modes of an ion crystal. https://arxiv.org/abs/2504.00590

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