Laser-Induced Quenching of the Th-229 Nuclear Clock Isomer in Calcium Fluoride

E. Peik; F. Schaden; G.A. Kazakov; G. Zitzer; I. Morawetz; J. Tiedau; K. Beeks; K. Zhang; L. Toscani De Col; M.V. Okhapkin

REVIEW 3 major objections 4 minor 38 references

Laser-Induced Quenching of the Th-229 Nuclear Clock Isomer in Calcium Fluoride

T0 review · 3 major / 4 minor · reviewed 2026-08-11 · deepseek-v4-flash

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Pith's one-line read This paper demonstrates that off-resonant laser light can accelerate the decay of the thorium-229 nuclear isomer in calcium fluoride by up to a factor of three, providing a tabletop ground-state initialization mechanism for a solid-state…

desk verdict First experimental demonstration of laser-induced quenching of the 229Th isomer in CaF2, with solid internal consistency but a quantitative blind-window caveat that needs a control. read the letter →

arxiv 2412.12339 v1 pith:Q4AHTCKC submitted 2024-12-16 physics.atom-ph cond-mat.othernucl-exquant-ph

F. Schaden , T. Riebner , I. Morawetz , L. Toscani De Col , G.A. Kazakov , K. Beeks , T. Sikorsky , T. Schumm

show 6 more authors

K. Zhang V. Lal G. Zitzer J. Tiedau M.V. Okhapkin E. Peik

This is my paper · ORCID

classification physics.atom-phcond-mat.othernucl-exquant-ph

keywords thorium-229nuclearclocklaser-inducedquenchingcalciumfluoridesolid-stateisomerdepumpinginternalconversionVUVspectroscopy

verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper reports a new experimental method, laser-induced quenching (LIQ), that forces the 10-minute metastable nuclear isomer state of thorium-229 in a calcium fluoride crystal to decay up to three times faster than its natural radiative lifetime. Because the thorium-229 isomer is the basis of a proposed solid-state nuclear clock, and because the 4+ electronic configuration blocks standard optical state readout and initialization, the long 600-second decay has been a bottleneck for clock operation. The authors show that off-resonant light between 148 nm and 420 nm, with only tens of milliwatts of power, depumps the isomer population, and that the effect is temperature-activated, disappearing below about 100 K and at infrared wavelengths. If correct, LIQ provides a tabletop way to reset the nuclear state each clock cycle, shortening interrogation cycles and improving clock stability.

What carries the argument

The central machinery is the two-level rate-equation model of the isomer population, $n_{\mathrm{isomer}}(t) \approx W\tau\left(1 - e^{-t/\tau}\right)$ with $\tau = 1/(\gamma_0 + \gamma_q)$, where $\gamma_0$ is the radiative decay rate and $\gamma_q$ is the laser-induced quenching rate. In the off-resonant scheme, the quench rate is inferred from the extra attenuation of the fluorescence decay measured before and after a window of intense off-resonant illumination. The physical agent remains unidentified, but the paper's analysis shows that LIQ requires a photon of roughly 2 eV energy and thermal activation of order 0.02 eV, pointing to laser-generated lattice defects or phonon-assisted internal conversion as candidate mechanisms.

What would settle it

Measure the isomer population continuously during the irradiation window using a detection method that rejects stray light, such as gated single-photon counting or a probe-and-repump scheme; if the decay during the window is not a single exponential with $\tau < \tau_0$, the threefold reduction is an artifact of the switch transients. Also, test the proposed wavelength threshold by looking for LIQ at 729 nm with higher power or improved beam overlap; any observed quenching there would contradict the claimed sharp cutoff.

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Extended reading notes

Core claim

The central claim is that visible-to-VUV laser light, far detuned from the nuclear resonance, accelerates the decay of the 229Th isomer in CaF2 via a non-resonant, thermally activated process. The authors demonstrate this with two complementary measurements: the excitation dynamics at room temperature show an extracted time constant of τ = 236(10) s versus the unperturbed value of τ0 = 618(9) s, and explicit off-resonant irradiation after excitation shortens the decay during the irradiation window. The quenching is independent of wavelength between 148 nm and 420 nm, scales roughly linearly with laser power, and is suppressed at low temperature; at 729 nm and longer, no quenching is seen. The paper presents LIQ as an effective depumping method for initializing the nuclear ground state in a solid-state nuclear clock.

Load-bearing premise

The reduced lifetime during the laser-irradiation window is inferred from fluorescence measured only before and after the window, assuming the decay stays a single exponential with constant detection efficiency across the on/off boundaries.

Editorial extensions

If this is right

LIQ enables ground-state initialization of the 229Th isomer in CaF2 without X-rays, directly shortening the interrogation cycle of a solid-state nuclear clock and potentially improving its stability.
The wavelength independence from 148 nm to 420 nm and the absence of quenching at 729 nm and beyond imply an energy threshold in the visible range for the depumping process.
The thermal activation of LIQ, fully suppressed at 100 K, means that cooling the crystal can protect the isomer population from unintentional laser-induced decay during excitation.
The observed reduction of fluorescence yield with temperature suggests that a competing decay channel is active during excitation, consistent with LIQ occurring even under resonant VUV irradiation.
Past failures to excite and detect the isomer with broadband VUV synchrotron sources may be explained by LIQ from off-resonant photons, and future broadband or multi-photon excitation schemes should include crystal cooling or non-resonant photon suppression.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

If LIQ arises from laser-generated defect states, the quenching rate should depend on accumulated laser dose and crystal history; this can be tested by comparing freshly fluorinated crystals with aged ones across repeated irradiation cycles.
The abrupt wavelength cutoff near the visible range suggests a two-step process: a single photon of about 2 eV creates a mobile defect or excitation that then opens a non-radiative decay channel; a sub-threshold or two-photon version of this process should be observable at higher intensities or with heating.
For other host crystals such as LiSAF, the same LIQ mechanism may either assist or sabotage nuclear clock operation, so broadband excitation sources may need spectral filtering and cooling to avoid accidental quenching in future solid-state nuclear clock designs.
A direct microscopic probe, such as monitoring defect-related absorption or luminescence during the quenching window, could distinguish between the defect-mediated and phonon-mediated explanations proposed in the paper.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Desk Editor's Note

read the letter

First real thing to know: this paper reports the first experimental evidence that off-resonant laser light can shorten the 229Th isomer lifetime in CaF2, with a systematic study over wavelength, power, and temperature. That is a new and useful result for the solid-state nuclear clock program, and the authors are honest that the underlying mechanism (likely defect-mediated internal conversion) is not yet pinned down.

What it does well: the central observation is supported by two independent protocols. The excitation-dynamics data (Fig. 3) show the build-up time constant dropping from ~617 s at 100 K to ~236 s at 297 K during resonance excitation, with no blind window. The off-resonance scheme (Fig. 4) then shows the same quenching after excitation, with a wavelength threshold between 420 and 729 nm and full suppression at 100 K. That internal consistency is the paper's strength. The clock-cycle analysis (Fig. 7) is sensible and gives the application motivation.

The soft spots are mostly quantitative. In the off-resonance scheme the PMT is blinded during irradiation, so the reduced lifetime in the shaded window is inferred from the pre- and post-irradiation exponentials, not measured directly. That opens the door to a detection-efficiency step masquerading as faster decay. The stress-test note makes this point well, but I don't think it sinks the paper: a pure efficiency artifact would not so cleanly vanish at 729 nm or at 100 K, and the excitation-dynamics data are independent of the blind window. Still, the authors should add a control—e.g., measuring a known-stable source through the same sequence, or repeating after irradiation to check for permanent changes in crystal transmission—and they should state the systematic uncertainty on the inferred tau during the window.

Minor issues: the abstract says 20 mW and the main text says 30 mW for the same factor-of-three claim; figures have no error bars; the wavelength-power comparison is weakened by acknowledged up to 50% beam-overlap uncertainty, which makes the "wavelength-independent" claim softer than it reads.

Who is this for: anyone working on 229Th solid-state clocks or on nuclear-crystal interactions. A serious referee should get it; with the efficiency control and a cleaned-up quantitative comparison, it is a solid experimental paper.

Referee Report

3 major / 4 minor

Summary. The manuscript reports experimental evidence for laser-induced quenching (LIQ) of the 229Th isomer in 229Th:CaF2. The authors measure the unperturbed radiative lifetime τ0 = 618(9) s over 100–350 K. They then report two types of quenching observations: (i) during on-resonance VUV excitation, the population rise time shortens at 297 K (τ = 236(10) s) compared with 100 K (τ = 617(19) s), and (ii) in an off-resonance protocol, the decay after a period of off-resonant laser irradiation appears accelerated, yielding an inferred reduced lifetime τ < τ0. They map this effect versus temperature and laser wavelength/power, report wavelength-independent quenching between 148 and 420 nm, absence of quenching at 729/840 nm, and discuss implications for a solid-state nuclear clock.

Significance. If the effect is real, LIQ would be a valuable tool for ground-state initialization in a solid-state 229Th nuclear clock, and the observation of temperature-activated, wavelength-independent quenching with a photon-energy threshold near 2 eV is interesting and constrains models of defect-mediated internal conversion. The paper is honest about the unknown mechanism and about beam-overlap uncertainties, and it provides a direct excitation-dynamics data point (Fig. 3) that is not subject to the off-resonance blind-window issue. However, the headline quantitative claims (factor-of-three lifetime reduction, wavelength independence) rest on the off-resonance protocol of Fig. 4, in which the decay during irradiation is inferred rather than measured. The manuscript does not provide controls for a laser-induced step in detection efficiency, which would produce the same signature. If the authors can supply such controls or appropriately weaken the quantitative claims, the core observation would be a useful contribution.

major comments (3)

[Off-resonance protocol (Fig. 4)] The reduced lifetime τ < τ0 in the shaded window of Fig. 4 is inferred by connecting the pre- and post-irradiation τ0 exponentials, and the text states 'No fluorescence signal could be taken during the off-resonant laser irradiation period because of stray light blinding the PMT.' This inference assumes detection efficiency is identical before and after the irradiation window. If the quenching laser causes a step-like change in collection efficiency f (e.g., transient PMT recovery, laser-induced color centers absorbing the 148 nm fluorescence, or changes in crystal transmission), the after-amplitude satisfies A_after = A_before exp(-T/τ0) f, and the inferred lifetime satisfies exp(-T/τ) = f exp(-T/τ0), giving τ < τ0 whenever f < 1. A factor-of-three apparent shortening can therefore be produced entirely by a detection-efficiency step with no accelerated nuclear decay. The after-curve being a τ0 exponential only shows that the decay constant after the window is unchanged; it does not constrain the population at the end of the window relative to the start. This confound is not remote: the paper itself proposes laser-induced defect centers as the LIQ mechanism, and the SM notes that C10 required refurbishment after VUV-induced damage. Because the temperature, power, and wavelength dependences in Figs. 5 and 6 are all obtained with this protocol, the quantitative central claims inherit this uncertainty. Please provide controls (e.g., monitoring PMT counts from a stable source through the irradiation window, or measuring crystal transmission before/after irradiation) or restrict the quantitative claims to the directly measured excitation dynamics.
[Power dependence and wavelength independence (Fig. 6)] The claim of wavelength independence between 148 and 420 nm is weakened by the acknowledged up-to-50% uncertainty in effective power due to beam overlap: the text states 'it is impossible to give a precise quantitative comparison between different lasers.' With a single VUV power point and a sparse set of wavelengths and powers, the data are consistent with a common curve but do not strongly constrain a wavelength-dependent efficiency. Please either provide a calibration of the beam overlap for each wavelength or soften the claim to 'consistent with wavelength independence within the present power-calibration uncertainty.'
[Abstract and main text] The abstract states 'achieving a threefold reduction in the isomer lifetime with 20 mW of laser power,' while the main text states 'up to three times faster at 297 K using 30 mW of average laser power.' This is a direct quantitative inconsistency in the headline result. Please correct the discrepancy and specify which data point in Fig. 6 corresponds to the factor-of-three reduction.

minor comments (4)

[Fig. 4] Please describe the fitting procedure used to extract τ in the shaded window from the pre- and post-irradiation segments, and report the uncertainty on that inferred lifetime.
[Fig. 5] The common-slope fits in Fig. 5 are described as guides to the eye; please state explicitly in the main text that these fits are not used for any quantitative extraction, to avoid confusion with an activation-energy measurement.
[Fig. 2 inset] The inset would be easier to assess if individual temperature points with error bars were shown rather than only a mean line and standard-deviation band.
[Production quality] In the version I received, several figure captions and equations contain corrupted '/uni...' fragments; please ensure the production PDF renders these correctly.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the LIQ lifetimes are measured observables extracted with a standard two-level rate-equation model, not predictions reduced to fitted inputs or to self-citations.

full rationale

The paper's derivation chain is experimental rather than self-referential. The central quantity τ is obtained by exponential fits to measured excitation or decay curves: main-text Eq. (1) and SM Eq. (3) are the standard two-level rate equation n₂(t) ≈ Wτ(1−e^(−t/τ)) with W ≪ γ, so τ is a fit parameter of independently recorded fluorescence data, not a quantity defined in terms of the LIQ claim. The unperturbed lifetime τ0 = 618(9) s is measured separately and agrees with prior work, so the comparison τ < τ0 is not built into the fit. The common slope of −1.5 s/K in Fig. 5 is explicitly only a guide to the eye and does not enter the central claim. The off-resonance scheme infers τ < τ0 in the dark irradiation window by connecting the pre- and post-window exponential decays; this assumes constant detection efficiency and a single exponential through the window, which is a systematic/modelling concern rather than a circular reduction, because the paper does not define LIQ as the amplitude drop nor fit the quenching rate to the very quantity it reports as evidence. Self-citations to prior work ([19], [21], [24]) provide context, an independent X-ray-quenching measurement, and a proposed microscopic mechanism; none is used as a uniqueness theorem, as an ansatz smuggled in by authority, or to forbid alternative explanations of the data. No fitted parameter is renamed as a prediction, and no result is equivalent to its input by construction.

Assumptions & free parameters 1 free parameters · 4 assumptions · 0 invented entities

The paper is an experimental demonstration, not a derivation. No new particles, forces, or conserved quantities are introduced. The only free parameter is a visualization slope. The model assumptions are standard rate equations, fluorescence proportionality, off-resonance behavior, and thermal uniformity; none are circular.

free parameters (1)

Common slope of temperature-lifetime fits = -1.5 s/K
In Fig. 5, linear fits to the tau(T) data are imposed with an identical slope of -1.5 s/K across crystals and laser sources. This is a hand-set guide-to-the-eye parameter, not a derived or independently verified quantity.

assumptions (4)

domain assumption The isomer population follows the two-level rate equation n(t) approx W*tau*(1 - e^(-t/tau)) with W << gamma (SM Eq. 3).
Used to extract tau from excitation build-up and steady-state signal; assumes constant excitation rate and that the only decay channels are radiative plus quenching.
domain assumption Nuclear fluorescence intensity is proportional to isomer population and detection efficiency is constant over each decay record.
Underlies all exponential lifetime fits, including the pre/post irradiation inference in Fig. 4. If detection efficiency changes after intense laser exposure, the inferred tau is biased.
domain assumption A VUV laser detuned by about 100 GHz does not resonantly excite the isomer.
Used in the off-resonance scheme; if false, the observed population loss could be an excitation artifact rather than quenching.
domain assumption Crystal temperature is uniform and controlled, with no significant local laser heating that mimics thermal activation.
The LIQ temperature dependence is interpreted as an intrinsic thermal activation; unmeasured local heating would change the interpretation and the apparent threshold near 100 K.

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Cite this review

Pith. "Pith review of Laser-Induced Quenching of the Th-229 Nuclear Clock Isomer in Calcium Fluoride." pith.science (2026). https://pith.science/paper/Q4AHTCKC

@misc{pith2026241212339,
  author       = {Pith},
  title        = {Pith review of: Laser-Induced Quenching of the Th-229 Nuclear Clock Isomer in Calcium Fluoride},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/Q4AHTCKC}},
  note         = {Machine review of arXiv:2412.12339}
}

abstract

The 10-minute radiative lifetime of the first excited $^{229}$Th$^{4+}$ nuclear state in ionic crystals provides narrow spectroscopic linewidths, enabling the realization of a solid-state nuclear clock. Due to the 4+ noble gas configuration, electronic readout or state initialization schemes known from atomic clocks are inaccessible. This elongates the interrogation cycle, which will deteriorate the clock performance. To address this limitation we demonstrate laser-induced quenching (LIQ) as a method of depumping the $^{229}$Th isomer population in CaF$_2$. We provide experimental evidence for LIQ at different wavelengths (148 - 420 nm) and temperatures (100 - 350 K), achieving a threefold reduction in the isomer lifetime with 20 mW of laser power.

Figures

Figures reproduced from arXiv: 2412.12339 by the authors.

**Figure 1.** FIG. 1. Laser spectroscopy setup and the processed nuclear [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗

**Figure 4.** FIG. 4. Quenching of the [PITH_FULL_IMAGE:figures/full_fig_p003_4.png] view at source ↗

Figures from the paper (2 more)

**Figure 6.** Figure 6: FIG. 6. Off-resonant LIQ in the X2 crystal at different laser [PITH_FULL_IMAGE:figures/full_fig_p004_6.png]

**Figure 7.** Figure 7: FIG. 7. Ratio of fractional frequency instabilities of a [PITH_FULL_IMAGE:figures/full_fig_p004_7.png]

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Works this paper leans on

38 extracted references · 23 canonical work pages

[1]

Beeks, T

K. Beeks, T. Sikorsky, T. Schumm, J. Thielking, M. V. Okhapkin, and E. Peik, Nature Reviews Physics 3, 238 (2021)

2021
[2]

Tiedau, M

J. Tiedau, M. Okhapkin, K. Zhang, J. Thielk- ing, G. Zitzer, E. Peik, F. Schaden, T. Pronebner, I. Morawetz, L. T. De Col,et al., Physical Review Letters 132, 182501 (2024)

work page 2024
[3]

Elwell, C

R. Elwell, C. Schneider, J. Jeet, J. E. S. Terhune, H. W. T. Morgan, A. N. Alexandrova, H. B. Tran Tan, A. Derevianko, and E. R. Hudson, Phys. Rev. Lett. 133, 013201 (2024)

2024
[4]

Kraemer, J

S. Kraemer, J. Moens, M. Athanasakis-Kaklamanakis, S. Bara, K. Beeks, P. Chhetri, K. Chrysalidis, A. Claessens, T. E. Cocolios, J. G. Correia, et al., Nature 617, 706 (2023)

2023
[5]

Yamaguchi, Y

A. Yamaguchi, Y. Shigekawa, H. Haba, H. Kikunaga, K. Shirasaki, M. Wada, and H. Katori, Nature , 1 (2024)

work page 2024
[6]

Zhang, L

C. Zhang, L. von der Wense, J. F. Doyle, J. S. Hig- gins, T. Ooi, H. U. Friebel, J. Ye, R. Elwell, J. Ter- hune, H. Morgan, et al., arXiv preprint arXiv:2410.01753 (2024)

arXiv 2024
[7]

Zhang, T

C. Zhang, T. Ooi, J. S. Higgins, J. F. Doyle, L. von der Wense, K. Beeks, A. Leitner, G. A. Kazakov, P. Li, P. G. Thirolf, et al., Nature 633, 63 (2024)

2024
[8]

Tkalya, V

E. Tkalya, V. Varlamov, V. Lomonosov, and S. Nikulin, Physica Scripta 53, 296 (1996)

1996

Show all 38 references

[9]

Tkalya, Physical review letters 106, 162501 (2011)

E. Tkalya, Physical review letters 106, 162501 (2011)

2011
[10]

Tkalya, P

E. Tkalya, P. Borisyuk, M. Domashenko, and Y. Y. Lebedinskii, arXiv preprint arXiv:2210.02512 (2022)

2022 arXiv
[11]

Peik and C

E. Peik and C. Tamm, Europhysics Letters 61, 181 (2003)

2003
[12]

E. Peik, T. Schumm, M. Safronova, A. Palffy, J. Weiten- berg, and P. G. Thirolf, Quantum Science and Technol- ogy 6, 034002 (2021)

2021
[13]

C. J. Campbell, A. G. Radnaev, A. Kuzmich, V. A. Dzuba, V. V. Flambaum, and A. Derevianko, Phys. Rev. Lett. 108, 120802 (2012)

2012
[14]

Fadeev, J

P. Fadeev, J. C. Berengut, and V. V. Flambaum, Phys- ical Review A 102, 052833 (2020)

2020
[15]

Caputo, D

A. Caputo, D. Gazit, H.-W. Hammer, J. Kopp, G. Paz, G. Perez, and K. Springmann, arXiv preprint arXiv:2407.17526 (2024)

2024 arXiv
[16]

Beeks, G

K. Beeks, G. A. Kazakov, F. Schaden, I. Morawetz, L. T. de Col, T. Riebner, M. Bartokos, T. Siko- rsky, T. Schumm, C. Zhang, et al. , arXiv preprint arXiv:2407.17300 (2024)

2024 arXiv
[17]

Banks, E

H. Banks, E. Fuchs, and M. McCullough, arXiv preprint arXiv:2407.11112 (2024)

2024 arXiv
[18]

Fuchs, F

E. Fuchs, F. Kirk, E. Madge, C. Paranjape, E. Peik, G. Perez, W. Ratzinger, and J. Tiedau, arXiv preprint arXiv:2407.15924 (2024). 6

2024 arXiv
[19]

Kazakov, A

G. Kazakov, A. Litvinov, V. Romanenko, L. Yat- senko, A. Romanenko, M. Schreitl, G. Winkler, and T. Schumm, New Journal of physics 14, 083019 (2012)

2012
[20]

B. S. Nickerson, M. Pimon, P. V. Bilous, J. Gugler, G. A. Kazakov, T. Sikorsky, K. Beeks, A. Gr¨ uneis, T. Schumm, and A. P´ alffy, Physical Review A103, 053120 (2021)

2021
[21]

Hiraki, K

T. Hiraki, K. Okai, M. Bartokos, K. Beeks, H. Fujimoto, Y. Fukunaga, H. Haba, Y. Kasamatsu, S. Kitao, A. Leit- ner, et al., Nature Communications 15, 5536 (2024)

2024
[22]

Porsev, V

S. Porsev, V. Flambaum, E. Peik, and C. Tamm, Phys- ical review letters 105, 182501 (2010)

2010
[23]

B. S. Nickerson, M. Pimon, P. V. Bilous, J. Gugler, K. Beeks, T. Sikorsky, P. Mohn, T. Schumm, and A. P´ alffy, Physical Review Letters125, 032501 (2020)

2020
[24]

Nalikowski, V

K. Nalikowski, V. Veryazov, K. Beeks, T. Schumm, and M. Kro´ snicki, arXiv preprint arXiv:2410.00230 (2024)

2024 arXiv
[28]

J. S. Higgins, T. Ooi, J. F. Doyle, C. Zhang, J. Ye, K. Beeks, T. Sikorsky, and T. Schumm, arXiv preprint arXiv:2409.11590 (2024)

2024 arXiv
[30]

Santarelli, C

G. Santarelli, C. Audoin, A. Makdissi, P. Laurent, G. Dick, and A. Clairon, IEEE Transactions on Ultrason- ics, Ferroelectrics, and Frequency Control45, 887 (1998)

1998
[31]

Safronova, D

M. Safronova, D. Budker, D. DeMille, D. F. J. Kimball, A. Derevianko, and C. W. Clark, Reviews of Modern Physics 90, 025008 (2018)

2018
[32]

Rix, Radiation-induced defects in calcium fluoride and their influence on material properties under 193 nm laser irradiation, Ph.D

S. Rix, Radiation-induced defects in calcium fluoride and their influence on material properties under 193 nm laser irradiation, Ph.D. thesis, Mainz, Univ., Diss., 2011 (2011)

2011
[33]

Stellmer, G

S. Stellmer, G. Kazakov, M. Schreitl, H. Kaser, M. Kolbe, and T. Schumm, Phys. Rev. A 97, 062506 (2018)

2018
[34]

J. Jeet, C. Schneider, S. T. Sullivan, W. G. Rellergert, S. Mirzadeh, A. Cassanho, H. Jenssen, E. V. Tkalya, and E. R. Hudson, Physical Review Letters 114, 253001 (2015). Supplemental Material: F. Schaden, T. Riebner, I. Morawetz, L. Toscani De Col, G.A. Kazakov, K. Beeks, T. ...

2015 arXiv
[35]

Thielking, K

J. Thielking, K. Zhang, J. Tiedau, J. Zander, G. Zitzer, M. Okhapkin, and E. Peik, New Journal of Physics 25, 083026 (2023)

2023
[36]

Tiedau, M

J. Tiedau, M. Okhapkin, K. Zhang, J. Thielking, G. Zitzer, E. Peik, F. Schaden, T. Pronebner, I. Morawetz, L. T. De Col, et al. , Physical Review Letters 132, 182501 (2024)

2024
[37]

Beeks, T

K. Beeks, T. Sikorsky, V. Rosecker, M. Pressler, F. Schaden, D. Werban, N. Hosseini, L. Rudischer, F. Schneider, P. Berwian, et al. , Scientific Reports 13, 3897 (2023)

2023
[38]

Beeks, The nuclear excitation of Thorium-229 in the CaF2 environment: Development of a crystalline nuclear clock, Ph.D

K. Beeks, The nuclear excitation of Thorium-229 in the CaF2 environment: Development of a crystalline nuclear clock, Ph.D. thesis, Technische Universit¨ at Wien (2022)

2022
[39]

Beeks, T

K. Beeks, T. Sikorsky, F. Schaden, M. Pressler, F. Schnei- der, B. N. Koch, T. Pronebner, D. Werban, N. Hosseini, G. Kazakov, et al., Physical Review B 109, 094111 (2024)

2024
[40]

Elwell, C

R. Elwell, C. Schneider, J. Jeet, J. E. S. Terhune, H. W. T. Morgan, A. N. Alexandrova, H. B. Tran Tan, A. Dere- vianko, and E. R. Hudson, Phys. Rev. Lett. 133, 013201 (2024)

2024
[41]

Kraemer, J

S. Kraemer, J. Moens, M. Athanasakis-Kaklamanakis, S. Bara, K. Beeks, P. Chhetri, K. Chrysalidis, A. Claessens, T. E. Cocolios, J. G. Correia, et al. , Nature 617, 706 (2023)

2023
[42]

A. E. Siegman, Lasers (University Science Books, 1986)

1986

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.

[1] [1]

Beeks, T

K. Beeks, T. Sikorsky, T. Schumm, J. Thielking, M. V. Okhapkin, and E. Peik, Nature Reviews Physics 3, 238 (2021)

2021

[2] [2]

Tiedau, M

J. Tiedau, M. Okhapkin, K. Zhang, J. Thielk- ing, G. Zitzer, E. Peik, F. Schaden, T. Pronebner, I. Morawetz, L. T. De Col,et al., Physical Review Letters 132, 182501 (2024)

work page 2024

[3] [3]

Elwell, C

R. Elwell, C. Schneider, J. Jeet, J. E. S. Terhune, H. W. T. Morgan, A. N. Alexandrova, H. B. Tran Tan, A. Derevianko, and E. R. Hudson, Phys. Rev. Lett. 133, 013201 (2024)

2024

[4] [4]

Kraemer, J

S. Kraemer, J. Moens, M. Athanasakis-Kaklamanakis, S. Bara, K. Beeks, P. Chhetri, K. Chrysalidis, A. Claessens, T. E. Cocolios, J. G. Correia, et al., Nature 617, 706 (2023)

2023

[5] [5]

Yamaguchi, Y

A. Yamaguchi, Y. Shigekawa, H. Haba, H. Kikunaga, K. Shirasaki, M. Wada, and H. Katori, Nature , 1 (2024)

work page 2024

[6] [6]

Zhang, L

C. Zhang, L. von der Wense, J. F. Doyle, J. S. Hig- gins, T. Ooi, H. U. Friebel, J. Ye, R. Elwell, J. Ter- hune, H. Morgan, et al., arXiv preprint arXiv:2410.01753 (2024)

arXiv 2024

[7] [7]

Zhang, T

C. Zhang, T. Ooi, J. S. Higgins, J. F. Doyle, L. von der Wense, K. Beeks, A. Leitner, G. A. Kazakov, P. Li, P. G. Thirolf, et al., Nature 633, 63 (2024)

2024

[8] [8]

Tkalya, V

E. Tkalya, V. Varlamov, V. Lomonosov, and S. Nikulin, Physica Scripta 53, 296 (1996)

1996