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  • Letter
  • Open Access

Laser-induced quenching of the Th-229 nuclear clock isomer in calcium fluoride

F. Schaden, T. Riebner, I. Morawetz, L. Toscani De Col, G. A. Kazakov, K. Beeks, T. Sikorsky, and T. Schumm*

K. Zhang, V. Lal, G. Zitzer, J. Tiedau, M. V. Okhapkin, and E. Peik†

  • *Contact author: thorsten.schumm@tuwien.ac.at
  • †Contact author: ekkehard.peik@ptb.de
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Phys. Rev. Research 7, L022036 – Published 16 May, 2025

DOI: https://doi.org/10.1103/PhysRevResearch.7.L022036

Abstract

The 10-min radiative lifetime of the first excited Th4+229 nuclear state in ionic crystals provides narrow spectroscopic linewidths, enabling the realization of a solid-state nuclear clock. Due to the 4+ noble gas configuration, electronic readout or state initialization schemes known from atomic clocks are inaccessible. This elongates the interrogation cycle, which will deteriorate the clock performance. To address this limitation we demonstrate laser-induced quenching (LIQ) as a method of depumping the Th229 isomer population in CaF2. We provide experimental evidence for LIQ at different wavelengths (148–420 nm) and temperatures (100–350 K), achieving a threefold reduction in the isomer lifetime with 20 mW of laser power.

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Corrections

11 June, 2025

Correction: This paper should have published concurrently with J. E. S. Terhune et al., Phys. Rev. Res. 7, L022062 (2025).

Article Text

Supplemental Material

References (37)

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Information

Phys. Rev. Research 7, L022036– Published 16 May, 2025
  • Received 16 December 2024
  • Accepted 30 April 2025
  • Corrected 11 June 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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