A step closer to the nuclear clock

Oscillations in the atomic nucleus of thorium-229 to be used as pulse generator for future nuclear clocks

Precise time measurements play a vital role in our daily life. They allow reliable navigation and accurate experimenting and provide a basis for world-wide synchronized exchange of data. A team of researchers of PTB Braunschweig, Ludwig-Maximilians-Universität München (LMU), Johannes Gutenberg University Mainz (JGU), the Helmholtz Institute Mainz (HIM), and GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt now reports on a decisive step toward the potential development of a nuclear clock, which bears the potential to significantly outperform the best current atomic clocks. The only known excited state of an atomic nucleus that is located at a suitably low excitation energy to be accessible by optical techniques, as they are in use in current atomic clocks, exists in thorium-229. Fundamental properties of thorium-229 in this state have now been determined, the researchers report in the current issue of the journal Nature.

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Johannes Thielking1, Maxim V. Okhapkin1, Przemysław Głowacki1, David M. Meier1, Lars von der Wense2, Benedict Seiferle2, Christoph E. Düllmann3,4,5, Peter G. Thirolf2 & Ekkehard Peik1
Laser spectroscopic characterization of the nuclear clock isomer 229mTh
Nature, 556, 321-325 (2018)
DOI: 10.1038/s41586-018-0011-8
*Corresponding author

Involved Institutes
  1. Physikalisch-Technische Bundesanstalt (PTB), Braunschweig
  2. Ludwig-Maximilians-Universität München (LMU), Garching
  3. GSI Helmholzzentrum für Schwerionenforschung GmbH, Darmstadt
  4. Helmholtz Institut Mainz (HIM), Mainz
  5. Johannes Gutenberg Universität Mainz, Mainz