Observation of a narrow inner-shell orbital transition in atomic erbium at 1299 nm

@Article{patscheider2021observation,
  title = {Observation of a narrow inner-shell orbital transition in atomic erbium at 1299 nm},
  author = {A. Patscheider and B. Yang and G. Natale and D. Petter and L. Chomaz and M. J. Mark and G. Hovhannesyan and M. Lepers and F. Ferlaino},
  journal = {Phys. Rev. Research},
  volume = {3},
  issue = {3},
  pages = {033256},
  numpages = {12},
  year = {2021},
  month = {Sep},
  publisher = {American Physical Society},
  doi = {10.1103/PhysRevResearch.3.033256},
  url = {https://link.aps.org/doi/10.1103/PhysRevResearch.3.033256},
      abstract={We report on the observation and coherent excitation of atoms on the narrow inner-shell orbital transition, connecting the erbium ground state [Xe]4f12(3H6)6s2 to the excited state [Xe]4f11(4I15/2)05d(5D3/2)6s2(15/2,3/2)07. This transition corresponds to a wavelength of 1299 nm and is optically closed. We perform high-resolution spectroscopy to extract the gJ-factor of the 1299-nm state and to determine the frequency shift for four bosonic isotopes. We further demonstrate coherent control of the atomic state and extract a lifetime of 178(19) ms which corresponds to a linewidth of 0.9(1) Hz. The experimental findings are in good agreement with our semi-empirical model. In addition, we present theoretical calculations of the atomic polarizability, revealing several different magic-wavelength conditions. Finally, we make use of the vectorial polarizability and confirm a possible magic wavelength at 532 nm.},
      archivePrefix={arXiv:2105.01438},
      arXiv = {https://arxiv.org/abs/2105.01438},  
      primaryClass={physics.atom-ph}
}