Hyperfine Rovibrational States of in a Weak External Magnetic Field
Phys. Rev. Lett. 135, 043003 – Published 22 July, 2025
DOI: https://doi.org/10.1103/lclp-852d
Abstract
Rovibrational energies, wave functions, and Raman transition moments are reported for the lowest-energy states of the molecular ion including the magnetic couplings of the proton spins and molecular rotation in the presence of a weak external magnetic field. The rovibrational-hyperfine-Zeeman Hamiltonian matrix is constructed and diagonalized using the rovibrational eigenstates and the proton spin functions. The developed methodology can be used to compute hyperfine-Zeeman effects also for higher-energy rovibrational excitations of and other closed-shell polyatomic molecules. These developments will guide future experiments extending quantum logic spectroscopy to polyatomic systems.