Toward direct VUV frequency comb spectroscopy of the <sup>229m</sup>Th nuclear state

ORAL

Abstract

Recent breakthroughs searching for the low-energy 229mTh isomeric state have constrained its energy range to 8.12 ± 0.11 eV, within the reach of state-of-the-art VUV frequency combs. Direct VUV frequency comb spectroscopy of the 229mTh isomeric state in the ongoing experiment at JILA promises a further reduction of its energy uncertainty by 6 orders of magnitude, making it possible to develop a nuclear-based optical clock. In neutral atoms, the 229mTh state decays dominantly via the internal-conversion channel with a lifetime of about 10 us. Using this decay channel, we designed our experiment for optical excitation of the isomeric state on a thin (10 nm) 229Th layer deposited on a metallic substrate irradiated by the JILA VUV frequency comb. We will present our progress in this experimental effort.

*This work is supported by AFOSR Grant No. FA9550- 19-1-0148, ARO Grant No. W911NF2010182, NSF Grant No. PHY-1734006, and the National Institute of Standards and Technology.

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Publication: Published: von der Wense, L., Zhang, C. Concepts for direct frequency-comb spectroscopy of 229mTh and an internal-conversion-based solid-state nuclear clock. Eur. Phys. J. D 74, 146 (2020). https://doi.org/10.1140/epjd/e2020-100582-5

Submitted: Toward a Tunable VUV Frequency Comb for 229mTh Nuclear Spectroscopy, CLEO 2021 abstract

Presenters

  • Chuankun Zhang

    • JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA

Authors

  • Chuankun Zhang

    • JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA

  • Lars von der Wense

    • University of Colorado, Boulder
    • JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA

  • Peng Li

    • IMRA America, Inc., 1044 Woodridge Avenue, Ann Arbor, Michigan, 48105, USA

  • Jie Jiang

    • IMRA America, Inc., 1044 Woodridge Avenue, Ann Arbor, Michigan, 48105, USA

  • Martin E Fermann

    • IMRA America, Inc., 1044 Woodridge Avenue, Ann Arbor, Michigan, 48105, USA

  • Jun Ye

    • JILA and University of Colorado Boulder
    • JILA, University of Colorado, Boulder
    • University of Colorado, Boulder
    • JILA, NIST, and University of Colorado Boulder
    • JILA, University of Colorado Boulder
    • JILA, University of Colorado and National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
    • JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
    • JILA, NIST, and Department of Physics, University of Colorado, Boulder
    • JILA, NIST, and University of Colorado, Boulder
    • JILA, NIST, and University of Colorado at Boulder