Direct detection of the 229Th nuclear clock transition

  title={Direct detection of the 229Th nuclear clock transition},
  author={Lars von der Wense and Benedict Seiferle and Mustapha Laatiaoui and J{\"u}rgen B. Neumayr and Hans-J{\"o}rg Maier and H-F. Wirth and Ch. Mokry and J{\"o}rg Runke and Klaus Eberhardt and Christoph E D{\"u}llmann and Norbert Trautmann and Peter G Thirolf},
Today’s most precise time and frequency measurements are performed with optical atomic clocks. However, it has been proposed that they could potentially be outperformed by a nuclear clock, which employs a nuclear transition instead of an atomic shell transition. There is only one known nuclear state that could serve as a nuclear clock using currently available technology, namely, the isomeric first excited state of 229Th (denoted 229mTh). Here we report the direct detection of this nuclear… Expand

Figures and Topics from this paper

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
Nuclear physics: Elusive transition spotted in thorium
Direct detection of the thorium-229 nuclear-clock transition is achieved, placing new limits on the transition energy and measuring the state's half-life, and these results suggest that nuclear quantum optics and nuclear lasers based on this transition may be plausible possibilities. Expand
Direct Search for Low Energy Nuclear Isomeric Transition of Th-229m With TES Detector
Precise knowledge of the energy and lifetime of 229mTh isomeric state has notable importance as a basis for a nuclear clock. Such a clock would be capable to extend precision on the oscillatorExpand
Direct detection of the elusive 229thorium isomer: Milestone towards a nuclear clock
  • P. Thirolf, B. Seiferle, +9 authors N. Trautmann
  • Physics
  • 2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFC)
  • 2017
Recently, the first direct detection of the long-searched low-lying isomeric first excited state of 229Th could be realized via its internal conversion decay branch, which confirms the isomer'sExpand
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
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
Concepts for direct frequency-comb spectroscopy of 229mTh and an internal-conversion-based solid-state nuclear clock
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-dopedExpand
The thorium-229 low-energy isomer and the nuclear clock
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 theExpand
Towards a precise determination of the excitation energy of the Thorium nuclear isomer using a magnetic bottle spectrometer
Abstract 229Th is the only known nucleus with an excited state that offers the possibility for a direct laser excitation using existing laser technology. Its excitation energy has been measuredExpand
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


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
Constraining the evolution of the fundamental constants with a solid-state optical frequency reference based on the 229Th nucleus.
It is argued that the 229Th optical nuclear transition may be driven inside a host crystal with a high transition Q to allow for the construction of a solid-state optical frequency reference that surpasses the short-term stability of current optical clocks, as well as improved limits on the variability of fundamental constants. Expand
Nuclear clocks based on resonant excitation of γ-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 anExpand
Towards a direct transition energy measurement of the lowest nuclear excitation in229Th
The isomeric first excited state of the isotope 229Th exhibits the lowest nuclear excitation energy in the whole landscape of known atomic nuclei. For a long time this energy was reported in theExpand
Nuclear structure of 229 Th
Lifetimes of excited states in Th-229, populated in the beta decay of Ac-229, have been measured using the advanced time-delayed beta gamma gamma(t) method. Half-lives of 14 states have beenExpand
Systematic evaluation of an atomic clock at 2 × 10−18 total uncertainty
This work performs a new accuracy evaluation of the JILA Sr clock, reducing many systematic uncertainties that limited previous measurements, such as those in the lattice ac Stark shift, the atoms' thermal environment and the atomic response to room-temperature blackbody radiation. Expand
Single-ion nuclear clock for metrology at the 19th decimal place.
A virtual clock transition composed of stretched states within the 5F(5/2) electronic ground level of both nuclear ground and isomeric manifolds is proposed and is shown to offer unprecedented systematic shift suppression, allowing for clock performance with a total fractional inaccuracy approaching 1×10(-19). Expand
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
Observation of the Deexcitation of the Th 229 m Nuclear Isomer
The $^{229}\mathrm{Th}$ nucleus possesses the lowest-energy nuclear isomeric state. Two widely accepted indirect measurements of the transition energy place it within reach of existing laserExpand
Nuclear structure of 229,231Th studied with the 230,232Th(d,t) reactions
Abstract Detailed angular distributions for the 230,232Th( d , t )229,231Th reactions were measured with 17 MeV deuterons, using a magnetic spectrograph to analyze the reaction products. ComparisonsExpand