Towards a 229Th-Based Nuclear Clock

An overview of the current status of the development of a nuclear clock based on the state of lowest known nuclear excitation energy in 229Th is presented. The text is especially written for the interested reader without any particular knowledge in this field of research. It is thus ideal as an introductory reading to get a broad overview of the various different aspects of the field; in addition, it can serve as a guideline for future research. An introductory part is provided, giving a historic context and explaining the fundamental concept of clocks. Finally, potential candidates for nuclear clocks other than 229Th are discussed.

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Acknowledgements

This work was supported by the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 664732 “nuClock,” by DFG grant Th956/3-1, and by the LMU department of Medical Physics via the Maier-Leibnitz Laboratory. L.v.d.Wense would like to thank the organizers of the conference within the frame of the jubilee celebrating “175 years of the Mendeleev All-Russia Research Institute of Metrology (VNIIM) and National Measurement System” in St. Petersburg for the invitation.

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Correspondence to L. von der Wense.

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Published in Izmeritel’naya Tekhnika, No. 12, pp. 13–22, December, 2017.

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von der Wense, L., Seiferle, B. & Thirolf, P.G. Towards a 229Th-Based Nuclear Clock. Meas Tech 60, 1178–1192 (2018). https://doi.org/10.1007/s11018-018-1337-1

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Keywords

  • Nuclear Clock
  • Conversion Electron Mössbauer Spectroscopy (CEMS)
  • Direct Laser Excitation
  • Isomeric Decay
  • Optical Lattice Clock