Nuclear clocks based on resonant excitation of gamma-transitions

Abstract

We review the ideas and concepts for a clock that is based on a radiative transition in the nucleus rather than in the electron shell. This type of clock offers advantages like an insensitivity against field-induced systematic frequency shifts and the opportunity to obtain high stability from interrogating many nuclei in the solid state. Experimental work concentrates on the low-energy (about 8 eV) isomeric transition in Th-229. We review the status of the experiments that aim at a direct optical observation of this transition and outline the plans for high-resolution laser spectroscopy experiments.

arXiv commentInvited review paper for Comptes Rendus de Physique, thematic issue 'The Measurement of Time'

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Cited by in corpus (43)

• Search for New Physics with Atoms and Molecules
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• Laser spectroscopic characterization of the nuclear clock isomer ${}^{229m}$Th
• Measurement of the ${}^{229}$Th isomer energy with a magnetic micro-calorimeter
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• Recent progress in laser spectroscopy of the actinides
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• Excitation of ${}^{229m}$Th at Inelastic Scattering of Low Energy Electrons
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• Towards a 229Th-based nuclear clock
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• Hyperfine interaction with the ${}^{229}$Th nucleus and its low lying isomeric state
• Observation of an unexpected negative isotope shift in 229Th+ and its theoretical explanation
• Universal ultra-robust interrogation protocol with zero probe-field-induced frequency shift for quantum clocks and high-accuracy spectroscopy
• Theoretical analysis of the electron bridge process in ${}^{229}$Th${}^{3+}$
• A scheme for excitation of thorium-229 nuclei based on the electronic bridge excitaion
• Nuclear coherent population transfer to the ${}^{229m}$Th isomer using x-ray pulses
• Optical Transmission Enhancement of Ionic Crystals via Superionic Fluoride Transfer: Growing VUV-Transparent Radioactive Crystals
• Electronic level structure of ${\mathrm{Th}}^{+}$ in the range of the ${}^{229m}\mathrm{Th}$ isomer energy
• Magnetic hyperfine structure of the ground-state doublet in highly charged ions ${}^{229}$Th${}^{89+,87+}$ and the Bohr-Weisskopf effect
• Experimental studies of thorium ions implantation from pulse laser plasma into thin silicon oxide layers
• Collective effects in ${}^{229}$Th-doped crystals
• Towards an energy measurement of the internal conversion electron in the de-excitation of the Th-229 isomer
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• Studies of thorium and ytterbium ion trap loading from laser ablation for gravity monitoring with nuclear clocks
• Proposal for a Nuclear Light Source