Towards a measurement of the nuclear clock transition in 229Th

8th Symposium on Frequency Standards and Metrology 2015

Stellmer, Simon^1 ; Schreitl, Matthias^1 ; Kazakov, Georgy^1 ; Yoshimura, Koji^2 ; Schumm, Thorsten^1

Vienna Center for Quantum Science and Technology (VCQ) and Atominstitut, TU Wien, Vienna

1020, Austria^1

Research Core for Extreme Quantum World, University of Okayama, Okayama, Japan^2

关键词: Clock transition;    Isomeric state;    Optical clocks;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/723/1/012059/pdf
DOI  :  10.1088/1742-6596/723/1/012059

来源: IOP

【 摘 要 】

We investigate a potential candidate for a future optical clock: the nucleus of the isotope229Th. Over the past 40 years of research, various experiments have found evidence for the existence of an isomeric state at an energy of a few eV. So far, neither the energy nor the lifetime of the isomer have been determined directly. As the scene is not yet prepared for direct laser excitation, other means of populating the isomer need to be explored. We investigate three different approaches, all of which rely on CaF2crystals doped with229Th or233U. Various kinds of crystal luminescence are discussed in detail.