Concepts for direct frequency-comb spectroscopy of 229mTh and an internal-conversion-based solid-state nuclear clock

  title={Concepts for direct frequency-comb spectroscopy of 229mTh and an internal-conversion-based solid-state nuclear clock},
  author={Lars von der Wense and Chuankun Zhang},
  journal={European Physical Journal D},
A new concept for narrow-band direct nuclear laser spectroscopy of 229m Th is proposed, using a single comb mode of a vacuum ultraviolet frequency comb generated from the 7th harmonic of an Yb-doped fiber laser system. In this concept more than 1013 229 Th atoms on a surface are irradiated in parallel and a successful nuclear excitation is probed via the internal-conversion (IC) decay channel. A net scanning time of 15 min for the most recent 1σ energy uncertainty interval of 0.34 eV appears to… 
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