High-resolution direct optical frequency comb Raman spectroscopy of single ions: From atomic fine structures to rotational spectra of molecular ions

Research output: Contribution to book/anthology/report/proceedingArticle in proceedingsResearchpeer-review


Optical frequency combs have in the recent past revolutionized the field of high-resolution spectroscopy by being applied both as frequency references and light sources for direct comb spectroscopy. With respect to the latter application, we have demonstrated the use of an optical frequency comb to coherently drive stimulated Raman transitions between terahertz-spaced atomic energy levels. Specifically, we have measured the 3d 2D3/2 - 3d 2D5/2 fine structure splitting of a single trapped 40Ca+ ion to be 1,819,599,021,534±8Hz, which is five times more accurate than previous measurements, and currently only limited by the stability of our atomic clock reference. Furthermore, Rabi oscillations with a contrast of 99.3(6)% and millisecond coherence time have been realized experimentally, indicating great potentials for future qubit applications. Importantly, the technique should generally be applicable to drive Raman transitions spanning the level spacings ranging from sub-kHz to tens of THz range, including hyperfine transitions in highly charged ions and spin-resolved rovibrational transitions in molecular ions. High-resolution spectroscopy of such systems may find applications in the search for new physics beyond the Standard Model.

Original languageEnglish
Title of host publicationOptical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II
EditorsSelim M. Shahriar, Jacob Scheuer
Publication year2020
Article number112962A
ISBN (Electronic)9781510633551
Publication statusPublished - 2020
EventOptical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II 2020 - San Francisco, United States
Duration: 1 Feb 20206 Feb 2020


ConferenceOptical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II 2020
LandUnited States
BySan Francisco
SponsorThe Society of Photo-Optical Instrumentation Engineers (SPIE)
SeriesProceedings of SPIE - The International Society for Optical Engineering

    Research areas

  • high-resolution spectroscopy, laser-cooled ions, molecular ions, optical frequency combs, raman spectroscopy, trapped ions

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