The thorium-229 low-energy isomer and the nuclear clock

  title={The thorium-229 low-energy isomer and the nuclear clock},
  author={Kjeld Beeks and Tom{\'a}{\vs} {\vS}ikorsk{\'y} and Thorsten Schumm and Johannes Thielking and Maxim V. Okhapkin and Ekkehard Peik},
The 229Th nucleus has an isomeric state at an energy of about 8 eV above the ground state, several orders of magnitude lower than typical nuclear excitation energies. This has inspired the development of a field of low-energy nuclear physics in which nuclear transition rates are influenced by the electron shell. The low energy makes the 229Th isomer accessible to resonant laser excitation. Observed in laser-cooled trapped thorium ions or with thorium dopant ions in a transparent solid, the… Expand
1 Citations
Nuclear clocks for testing fundamental physics
The low-energy, long-lived isomer in 229Th, first studied in the 1970s as an exotic feature in nuclear physics, continues to inspire a multidisciplinary community of physicists. It has stimulatedExpand


Energy of the 229Th nuclear clock transition
The method combines nuclear and atomic physics measurements to advance precision metrology, and the findings are expected to facilitate the application of high-resolution laser spectroscopy on nuclei and to enable the development of a nuclear optical clock of unprecedented accuracy. Expand
X-ray pumping of the 229Th nuclear clock isomer
Active optical pumping is presented using narrow-band 29-kiloelectronvolt synchrotron radiation to resonantly excite the second excited state of 229Th, which then decays predominantly into the isomer, enabling accurate determination of the 229mTh isomer’s energy, half-life and excitation linewidth. Expand
Laser spectroscopic characterization of the nuclear-clock isomer 229mTh
The laser spectroscopic investigation of the hyperfine structure of the doubly charged 229mTh ion and the determination of the fundamental nuclear properties of the isomer, namely, its magnetic dipole and electric quadrupole moments, as well as its nuclear charge radius are presented. Expand
229Thorium-doped calcium fluoride for nuclear laser spectroscopy.
  • P. Dessovic, P. Mohn, +4 authors T. Schumm
  • Chemistry, Medicine
  • Journal of physics. Condensed matter : an Institute of Physics journal
  • 2014
Based on the electronic structure, the thorium nuclear quantum levels within the solid-state environment are estimated and a persistent large band gap is found and no additional electronic levels emerging in the middle of the gap due to the presence of the dopant should allow direct optical interrogation of the nuclear transition. Expand
Performance of a 229 Thorium solid-state nuclear clock
The 7.8 eV nuclear isomer transition in 229thorium has been suggested as a clock transition in a new type of optical frequency standard. Here we discuss the construction of a ‘solid-state nuclearExpand
Nuclear laser spectroscopy of the 3.5 eV transition in Th-229
We propose high-resolution laser spectroscopy of the 3.5 eV nuclear transition in Th-229 in isolated atoms. Laser excitation of the nucleus can be detected efficiently in a double-resonance method byExpand
229DFT calculation of Thorium-doped Magnesium Fluoride for Nuclear Laser Spectroscopy.
Using the Vienna Ab-initio Simulation Package (VASP), density functional theory (DFT) calculations of the electronic and optical properties of Th:MgF2 determine whether Thorium will be accepted as a dopant and identify the charge compensation mechanism and geometry, and indicate, that the band gap of Th-doped M gF2 will be significantly reduced compared to undoped Mgf2, below the expected229Th isomer energy. Expand
Measuring the Th-229 nuclear isomer transition with U-233 doped crystals
We propose a simple approach to measure the energy of the few-eV isomeric state in Th-229. To this end, U-229 nuclei are doped into VUV-transparent crystals, where they undergo alpha decay intoExpand
Excitation of the Th229 nucleus via a two-photon electronic transition
We investigate the process of nuclear excitation via a two-photon electron transition (NETP) for the case of the doubly charged thorium. The theory of the NETP process has been devised originally forExpand
Nuclear excitation by electron transition and its application to uranium- 235 separation
A new mechanism for nuclear excitation is studied theoretically by considering the de­ excitation of electronic states of atom. When an electron of inner shells is kicked off by the bombardedExpand