The ${}^{229}$Th isomer: prospects for a nuclear optical clock

Abstract

The proposal for the development of a nuclear optical clock has triggered a multitude of experimental and theoretical studies. In particular the prediction of an unprecedented systematic frequency uncertainty of about $10^{-19}$ has rendered a nuclear clock an interesting tool for many applications, potentially even for a re-definition of the second. The focus of the corresponding research is a nuclear transition of the ${}^{229}$Th nucleus, which possesses a uniquely low nuclear excitation energy of only $8.12\pm 0.11$ eV ($152.7\pm 2.1$ nm). This energy is sufficiently low to allow for nuclear laser spectroscopy, an inherent requirement for a nuclear clock. Recently, some significant progress toward the development of a nuclear frequency standard has been made and by today there is no doubt that a nuclear clock will become reality, most likely not even in the too far future. Here we present a comprehensive review of the current status of nuclear clock development with the objective of providing a rather complete list of literature related to the topic, which could serve as a reference for future investigations.

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Cited by in corpus (13)

• Frequency ratio of the ${}^{229\mathrm{m}}$Th nuclear isomeric transition and the ${}^{87}$Sr atomic clock
• Observation of the radiative decay of the ${}^{229}\mathrm{Th}$ nuclear clock isomer
• Opportunities for Fundamental Physics Research with Radioactive Molecules
• Atlas of Nuclear Isomers -- Second Edition
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• Quantum Technology for Military Applications
• Theoretical evaluation of decay mode of ${}^{229m}\mathrm{Th}$ in solid samples