Pith. sign in

REVIEW 2 major objections 5 minor 1 cited by

Cryogenic Optical Lattice Clock with $1.7\times 10^{-20}$ Blackbody Radiation Stark Uncertainty

T0 review · 2 major / 5 minor · reviewed 2026-08-07 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗

Pith's one-line read A cryogenic ytterbium optical lattice clock reduces its blackbody-radiation shift uncertainty to $1.7\times10^{-20}$ by enclosing the atoms in a dynamically shuttered 77 K shield.

desk verdict A genuine advance in cryogenic BBR control, with a strong 1.7e-20 uncertainty claim and a useful direct Yb dynamic-coefficient measurement; the main soft spot is the simulation-dependent 2x gradient inflation factor. read the letter →

arxiv 2506.05304 v2 pith:FVXBUATD submitted 2025-06-05 physics.atom-ph

Youssef S. Hassan , Kyle Beloy , Jacob L. Siegel , Takumi Kobayashi , Eric Swiler , Tanner Grogan , Roger C. Brown , Tristan Rojo
show 4 more authors
Tobias Bothwell Benjamin D. Hunt Adam Halaoui Andrew D. Ludlow
This is my paper
classification physics.atom-ph
keywords cryogenicopticallatticeclockblackbodyradiationshiftytterbium-171StarkdynamicBBRcorrectionshieldatomicuncertainty
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

This paper reports a cryogenic optical lattice clock based on ytterbium-171 in which the blackbody-radiation (BBR) Stark shift is controlled to a fractional-frequency uncertainty of $1.7\times10^{-20}$, roughly 40 times smaller than the best prior optical lattice clock. The key move is a dynamically actuated radiation shield: during clock spectroscopy a rotating shutter sphere seals the atoms inside a near-isothermal 77 K enclosure, blocking external thermal radiation at the part-per-million level while preserving optical access for the lattice and clock beams. With the BBR environment under control, the authors vary the shield temperature from 77 K to 318 K and directly measure ytterbium's leading dynamic BBR correction, $\nu_{\mathrm{dyn},6} = -22.47(50)$ mHz, reducing the literature-combined uncertainty of that coefficient by 30%. If correct, the work removes BBR as the dominant systematic in cryogenic Yb clocks and sharpens the correction needed by room-temperature Yb clocks.

What carries the argument

The load-bearing object is the dynamically actuated shutter-sphere radiation shield. At its center sits a rotating copper sphere with apertures that align in the open configuration for atom loading and rotate shut in the closed configuration, leaving only a slit for the vertical lattice and co-propagating clock beam; a double stack of glass substrates blocks thermal radiation through that slit. The closed configuration surrounds the atoms over the full $4\pi$ solid angle with black-coated, temperature-servoed copper surfaces, and eight embedded RTDs plus thermal simulations bound the thermal extremes of every surface with direct line of sight to the atoms. The argument also uses the BBR shift model $\nu_{\mathrm{BBR}} = \nu_{\mathrm{stat}} t^4 + \nu_{\mathrm{dyn},6} t^6 + \nu_{\mathrm{dyn},8} t^8$, which lets the same apparatus measure both the static coefficient and the leading dynamic correction by controlled temperature variation.

What would settle it

Apply a controlled temperature offset to one stationary shield half while the clock runs at 77 K and compare the observed BBR shift change with the solid-angle-weighted prediction; a discrepancy larger than $1.6\times10^{-20}$ would falsify the thermal-gradient uncertainty estimate.

Watch

Extended reading notes

Core claim

The central claim is that a $^{171}$Yb optical lattice clock can be operated with a BBR Stark shift uncertainty of $1.7\times10^{-20}$ fractional frequency at a shield temperature of 77 K. This is achieved by a radiation shield whose rotating shutter sphere closes around the atoms during spectroscopy, so the atoms see only high-emissivity copper surfaces held at a common temperature, plus small doubly-windowed optical apertures that block external thermal radiation. Residual external radiation is bounded by reverse ray tracing to $4\times10^{-21}$; the dominant uncertainty, $1.6\times10^{-20}$, comes from thermal gradients across line-of-sight surfaces, inferred from eight embedded resistance temperature detectors (RTDs) and experiment-informed thermal simulations. The same uniform BBR environment, swept over temperature, yields a direct measurement of the leading dynamic correction $\nu_{\mathrm{dyn},6} = -22.47(50)$ mHz, and the weighted mean of the three Yb determinations is $\nu_{\mathrm{dyn},6} = -22.17(34)$ mHz, a 30% reduction in combined uncertainty. The static BBR coefficient is independently verified at the low $10^{-18}$ level against a previous polarizability measurement.

Load-bearing premise

The result rests on the premise that the eight embedded RTDs plus the experiment-informed thermal simulations correctly bound the temperature of every surface with direct line of sight to the atoms, including the factor-of-two inflation applied to the stationary shield's internal surfaces and electrodes.

Editorial extensions

If this is right

  • At 77 K the total BBR shift uncertainty of the Yb clock is $1.7\times10^{-20}$, about 40 times lower than the best previous optical lattice clock, so BBR ceases to be the limiting systematic for cryogenic operation.
  • The independent direct measurement of the leading dynamic BBR correction for ytterbium, $\nu_{\mathrm{dyn},6} = -22.47(50)$ mHz, combines with the two earlier determinations to a weighted mean of $-22.17(34)$ mHz, a 30% reduction in combined uncertainty.
  • The static BBR coefficient is confirmed at the low $10^{-18}$ level against an independent static-field polarizability measurement.
  • Because the shield is species-agnostic, the same design can provide near-ideal BBR environments for other optical lattice clock species, not just ytterbium.
  • At cryogenic temperatures the atomic-response contribution to BBR uncertainty drops below $10^{-21}$, leaving the remaining uncertainty purely environmental: thermal gradients and residual external radiation.

Reading between the lines

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

  • If the shuttering strategy is transferred to strontium or another lattice species, a similar gain should appear, because the limiting thermal-gradient uncertainty is geometric and thermometric rather than species-specific.
  • A natural next test is to add an independent thermometer at the atom location, such as a co-trapped species or a BBR-sensitive optical transition, and check the claimed 29 mK effective-temperature uncertainty.
  • At 300 K the improved dynamic-correction uncertainty corresponds to roughly $7\times10^{-19}$ fractional uncertainty, so previously published Yb clock accuracy budgets that used the older $\nu_{\mathrm{dyn},6}$ values may warrant re-evaluation.
  • The shield's wide temperature range makes it a possible calibration platform for measuring BBR response coefficients of other atomic species directly.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

2 major / 5 minor

Summary. The manuscript reports a cryogenic 171Yb optical lattice clock in which a dynamically actuated radiation shield encloses the atoms during spectroscopy, suppressing residual external thermal radiation and providing a controlled BBR environment at temperatures from 77 K to 318 K. The central claim is a total BBR Stark shift uncertainty of 1.7×10−20 at 77 K, about 40 times smaller than previous OLC values. The authors also extract the static BBR coefficient νstat = −1.2545(10) Hz from temperature-dependent clock comparisons and directly determine the leading dynamic BBR correction νdyn,6 = −22.47(50) mHz, whose weighted mean with two literature values is −22.17(34) mHz, a 30% uncertainty reduction.

Significance. The shield design is elegant and, if its uncertainty evaluation is sound, represents a substantial advance in BBR control for optical lattice clocks. The paper is careful in several respects: residual external radiation is bounded by reverse ray tracing with conservative emissivity and transmission assumptions and 100% uncertainty assignment; the temperature-gradient analysis uses contact thermometry with explicit solid-angle weighting; the νdyn,6 measurement is direct and independent of the earlier theoretical and semi-empirical determinations; and the background-gas collisional bias is bracketed by extreme cases. The main weakness is that the largest term in the 77 K budget rests on a factor-of-two extrapolation from embedded RTD readings to unmeasured internal shield surfaces via simulations calibrated to those same sensors, and that extrapolation is not independently verified in the final assembly.

major comments (2)
  1. [Supplemental Material, "Temperature deviations, (δνBBR)δT", Table II] At 77 K the "Temperature inhomogeneity (DLS surfaces)" term of 16×10−21 is the dominant contributor to the headline 17×10−21 total, and it is computed from temperature extremes [51, 248] mK for the shield halves and [96, 303] mK for the electrodes that are obtained from experiment-informed thermal simulations rather than from direct measurements in the final assembly. The text states that initial simulations agree with the RTD readings only within a factor of 2 and that the internal surfaces of the stationary shield, including the electrodes, are assigned temperature extremes 2× larger than the embedded sensors show; because the simulations are calibrated to the same eight RTDs, the factor 2 is not independently verified. If the true internal-surface extremes were 3–4× the sensor readings, a discrepancy within the stated factor-of-2 model-measurement agreement, the [51, 248] and [96, 303] mK ranges would widen and the 1.7×10−20 claim would no longer be conservative. Please provide an independent anchor for the internal-surface temperature extremes in the final assembly, or show explicitly how the headline uncertainty scales if the 2× inflation is replaced by 3× or 4×.
  2. [Supplemental Material, "Temperature-dependent background gas collision bias in determining νdyn,6"] The reported νdyn,6 value depends on the assumed temperature dependence of the background-gas collisional shift. The two bracketing cases use trap lifetimes of 25 s at all temperatures versus 100 s at 77 K, where the 100 s value is motivated by ideal-gas scaling rather than a direct cryogenic lifetime measurement; the resulting 0.53 mHz difference between the two fitted slopes is comparable to the fit uncertainty of 0.47 mHz and is only partially absorbed by the uniform-distribution inflation to 0.50 mHz. Since the 30% uncertainty reduction of the literature-combined νdyn,6 is a central secondary claim, the cryogenic lifetime or pressure assumption should be justified by direct measurement, or the sensitivity of the reported value to this assumption should be quantified more explicitly.
minor comments (5)
  1. [Main text, second paragraph after Fig. 1] The main text states an upper bound of 4×10−21 for the residual external radiation shift at 77 K, while Supplemental Table III sums to 3.3×10−21 in absolute value; please reconcile the two numbers or state explicitly that 4×10−21 is a rounded conservative value.
  2. [Supplemental Material, section title] The section title "T emperature deviations, (δνBBR)δT" contains a typographical space in "Temperature".
  3. [Supplemental Material, "The residual external thermal radiation leak"] The sentence "We now shift from the reverse ray tracing perspective ... we to the forward-in-time perspective" is missing a verb; please rephrase.
  4. [Supplemental Material, Table I discussion] In Table I the row "BBR Zeeman factor" lists an uncertainty budget entry, while the text emphasizes the magnitude of the BBR Zeeman shift itself; please make clear that the table entry is an uncertainty, not the shift, to avoid confusion.
  5. [Supplemental Material, "Estimating the thermal load on the shield"] The sentence "For all sensors on the shield, we immerse the sensor body in a hole drilled into the shield component and filled with perfluoropolyether (PFPE) based grease" is clear, but the earlier discussion of the warm-up ODE would benefit from stating explicitly which temperature sensor is used as the ODE variable before assigning it to the stationary shield mean.

Circularity Check

1 steps flagged · score 2.0 of 10

No forced equation-level circularity; the dynamic-coefficient and static-coefficient derivations are independent. One self-referential model validation, in which RTD-calibrated thermal simulations set the internal-surface temperature extremes, is the dominant-uncertainty soft spot and warrants a low non-zero score.

  1. other [Supplemental Material, 'Temperature deviations, (δνBBR)δT', Table II and preceding text]
    "The experiment-informed thermal simulations confirm that the RTDs faithfully represent the temperature extremes of the shutter sphere surfaces with direct line of sight to the atoms within 10%. For the stationary shield, the internal surfaces (including those of the electrodes) exhibit a 2× larger temperature extremes than seen by the embedded RTDs."

    The Table II ranges that set the dominant 1.6×10^-20 temperature-inhomogeneity uncertainty are 'retrieved from the experiment-informed thermal simulations.' Those simulations are informed by the same RTD data they are used to certify: 'We find that by simulating a 110 mW of thermal load at the tip reproduces the measured thermal differences of the RTDs embedded in the shutter sphere.' The 2× inflation for stationary-shield internal surfaces and the 10% fidelity claim for the shutter sphere are thus model outputs calibrated to the very sensors whose faithfulness they assert, not independently measured bounds.

full rationale

The central derivation chain is not circular. The headline 1.7×10^-20 claim is an error budget, not a fitted result: it combines RTD calibration and readout errors, a reverse-ray-tracing residual-radiation bound computed with deliberately conservative emissivities and transmission data, a BBR Zeeman term from tabulated polarizabilities, and the solid-angle-weighted temperature-inhomogeneity term of Eq. (5). The νdyn,6 = −22.47(50) mHz value is obtained from a direct global slope fit to measured Yb2-versus-reference frequency differences against (t^6_Yb2 − t^6_ref) in Eq. (2), with the fit uncertainty inflated by √χ²_red and by an explicit uniform-distribution model for possible background-gas bias; it is not fitted to the literature values it is later combined with, and the weighted mean with Refs. [9,10] (one of which is prior work by overlapping authors) is a comparison, not an input. The static-coefficient check is a free fit of νstat compared with the independent dc-field measurement of Ref. [20]. The one self-referential element is in the supplemental temperature-deviation analysis: the 'experiment-informed' thermal simulations used to set the Table II extremes are calibrated to the same RTD readings they are invoked to validate, and the electrodes were measured only in a temporary setup (Table II note). This is a real verification gap in the dominant 1.6×10^-20 term, but it is not an equation-level circular reduction; therefore the circularity score is low, with the caveat that the headline uncertainty is only as strong as the unverified 2× inflation factor.

Assumptions & free parameters 5 free parameters · 7 assumptions · 0 invented entities

The central 1.7e-20 uncertainty is an error budget built on direct RTD thermometry, conservative ray-tracing bounds, and worst-case thermal-gradient assumptions, with no fitted parameter determining the headline number. The νdyn,6 measurement is a slope fit to data, a legitimate measurement, though its systematic bounds rest on ad hoc case 0/case 1 scenarios. No invented physical entities appear.

free parameters (5)
  • νstat (static BBR coefficient) = -1.2545(10) Hz
    Fit of Eq. (1) to clock frequency differences at six Yb2 shield temperatures, fixing νdyn,6 and νdyn,8 to literature values. Used to verify the static BBR coefficient against Ref. [20]; not needed for the 1.7e-20 uncertainty claim.
  • νdyn,6 (leading dynamic correction) = -22.47(50) mHz
    Slope of Eq. (2) in a global fit to 25 interclock measurements. This is the directly measured secondary result; uncertainty is inflated by sqrt(reduced chi-squared) and a bounded background-gas systematic.
  • νc offsets for Yb2-Yb1 and Yb2-YbT = not stated
    Independent frequency offset terms in Eq. (2) for the two clock pairs; nuisance parameters in the νdyn,6 fit.
  • Aeff and k in thermal-load ODE = Aeff = 6.5(2)e-3 m^2, k = 7.4(3)e-3 W/K
    Fit of Eq. (8) to the shield warm-up curve; used to estimate radiative and conductive loads that inform the thermal simulations behind the temperature-extreme bounds.
  • Shutter-sphere tip heat load in simulation = 110 mW
    Chosen so the simulation reproduces the measured RTD temperature differences on the shutter sphere; this calibration loop underlies the claim that the RTDs capture the surface extremes.
assumptions (7)
  • domain assumption The tensor polarizabilities of the 171Yb clock states are identically zero, so the atoms sample the thermal radiation environment without directional bias and the BBR shift formula with scalar polarizability applies.
    Invoked in the Supplemental Material after Eq. (3) to justify ignoring anisotropy of the radiation environment; it is a standard angular-momentum selection rule for J=1/2 clock states.
  • domain assumption Internal shield surfaces can be modeled as opaque, Lambertian, blackbody surfaces with emissivities bounded by 0.8 at wavelengths below 100 µm and 0.2 above 100 µm.
    Used in the reverse ray-tracing estimate of residual external radiation (Supplement, 'The residual external thermal radiation leak'); the long-wavelength emissivity is an assumption because no coating data exist there.
  • domain assumption The aggregate N-BK7 transmission model t(λ), which assumes full transmission where no literature data exist, is an upper bound on the window transmission over the entire electromagnetic spectrum.
    Constructed in the Supplement from four literature sources and used in Eq. (7) to bound the leak through optical apertures.
  • ad hoc to paper The experiment-informed thermal simulations correctly predict the temperature extremes of all direct-line-of-sight surfaces, including a 2x inflation for the stationary shield internal surfaces relative to the embedded RTD readings.
    This is the load-bearing premise for the dominant 1.6e-20 uncertainty term; the simulations are calibrated with the same RTD measurements they are used to validate.
  • ad hoc to paper The background-gas collisional shift follows (Δν/ν)_BG = -1.64(12)e-17/τ, and the case 0 and case 1 trap-lifetime scenarios bracket the true temperature-dependent BG shift for the νdyn,6 measurement.
    Used in the Supplement to bound a possible bias in the dynamic-coefficient fit; the case 1 lifetimes (100 s, 25 s, 8 s) are chosen as conservative extremes rather than measured values.
  • domain assumption The two reference clocks Yb1 and YbT have no unaccounted temperature-dependent systematic shifts that would mimic a νdyn,6 slope in the differential measurements.
    The fits in Eq. (2) assume the frequency difference between clock pairs is dominated by the Yb2 BBR temperature dependence; agreement between the two reference clocks supports this.
  • domain assumption The BBR Zeeman shift can be evaluated using the magnetic dipole polarizabilities tabulated in Ref. [11] together with the Farley-Wing function for the dominant 3P0-3P1 coupling.
    Used in the Supplement to compute the small BBR Zeeman correction; the values are taken from a companion paper with overlapping authorship.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Cryogenic Optical Lattice Clock with $1.7\times 10^{-20}$ Blackbody Radiation Stark Uncertainty." pith.science (2026). https://pith.science/paper/FVXBUATD

@misc{pith2026250605304,
  author       = {Pith},
  title        = {Pith review of: Cryogenic Optical Lattice Clock with $1.7\times 10^-20$ Blackbody Radiation Stark Uncertainty},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/FVXBUATD}},
  note         = {Machine review of arXiv:2506.05304}
}
abstract

Controlling the Stark perturbation from ambient thermal radiation is key to advancing the performance of many atomic frequency standards, including state-of-the-art optical lattice clocks (OLCs). We demonstrate a cryogenic OLC that utilizes a dynamically actuated radiation shield to control the perturbation at $1.7\times10^{-20}$ fractional frequency, a factor of $\sim$40 beyond the best OLC to date. Our shield furnishes the atoms with a near-ideal cryogenic blackbody radiation (BBR) environment by rejecting external thermal radiation at the part-per-million level during clock spectroscopy, overcoming a key limitation with previous cryogenic BBR control solutions in OLCs. While the lowest BBR shift uncertainty is realized with cryogenic operation, we further exploit the radiation control that the shield offers over a wide range of temperatures to directly measure and verify the leading BBR Stark dynamic correction coefficient for ytterbium. This independent measurement reduces the literature-combined uncertainty of this coefficient by 30%, thus benefiting state-of-the-art Yb OLCs operated at room temperature. We verify the static BBR coefficient for Yb at the low $10^{-18}$ level.

Figures

Figures reproduced from arXiv: 2506.05304 by the authors.

Figure 1
Figure 1. FIG. 1. Illustrations of the shield structure and function. (a) Horizontal cross section at mid-plane of the shield. (i) Open [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. (a) Average of two simultaneous Rabi line scans on [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. (Top) Observed frequency difference between two [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figures from the paper (3 more)
Figure 4
Figure 4. Figure 4: FIG. 4. BBR spectrum at room temperature of [PITH_FULL_IMAGE:figures/full_fig_p010_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. (left) Location of the three RTDs embedded in the shutter sphere. Two RTDs are placed close to the coldest part of the [PITH_FULL_IMAGE:figures/full_fig_p018_5.png]
Figure 6
Figure 6. Figure 6: FIG. 6. Dynamic contribution to the BBR clock shift at 300 K for [PITH_FULL_IMAGE:figures/full_fig_p020_6.png]

Discussion (0). Sign in to comment.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Transportable strontium lattice clock with $4 \times 10^{-19}$ blackbody radiation shift uncertainty

    physics.atom-ph 2025-07 accept novelty 6.0 of 10

    A trailer-mounted 87Sr optical lattice clock reaches a 2.1×10^-18 total systematic uncertainty, with a 4.0×10^-19 blackbody radiation shift uncertainty enabled by a cold copper interrogation shield.

Reference graph

Works this paper leans on

42 extracted references · 42 canonical work pages · cited by 1 Pith paper

  1. [1]

    Itano, L

    Wayne M. Itano, L. L. Lewis, and D. J. Wineland. Shift of 2S 1 2 hyperfine splittings due to blackbody radiation. Phys. Rev. A , 25:1233–1235, Feb 1982

    work page 1982

  2. [2]

    Ludlow, Martin M

    Andrew D. Ludlow, Martin M. Boyd, Jun Ye, E. Peik, and P. O. Schmidt. Optical atomic clocks. Rev. Mod. Phys., 87:637–701, Jun 2015

    work page 2015

  3. [3]

    Shifts and uncertainties given without units are in frac- tional units of the respective clock frequency

    work page

  4. [4]

    W. F. McGrew, X. Zhang, R. J. Fasano, S. A. Sch¨ affer, K. Beloy, D. Nicolodi, R. C. Brown, N. Hinkley, G. Mi- lani, M. Schioppo, T. H. Yoon, and A. D. Ludlow. Atomic clock performance enabling geodesy below the centimetre level. Nature, 564:87–90, 2018

    work page 2018

  5. [5]

    Safronova, and Jun Ye

    Alexander Aeppli, Kyungtae Kim, William Warfield, Marianna S. Safronova, and Jun Ye. Clock with 8×10−19 systematic uncertainty. Phys. Rev. Lett., 133:023401, Jul 2024

    work page 2024

  6. [6]

    Beloy, N

    K. Beloy, N. Hinkley, N. B. Phillips, J. A. Sherman, M. Schioppo, J. Lehman, A. Feldman, L. M. Hanssen, C. W. Oates, and A. D. Ludlow. Atomic clock with 1×10−18 room-temperature blackbody Stark uncertainty. Phys. Rev. Lett. , 113:260801, Dec 2014

    work page 2014

  7. [7]

    J. A. Sherman, N. D. Lemke, N. Hinkley, M. Pizzocaro, R. W. Fox, A. D. Ludlow, and C. W. Oates. High- accuracy measurement of atomic polarizability in an opti- cal lattice clock. Phys. Rev. Lett., 108:153002, Apr 2012

    work page 2012

  8. [8]

    High accuracy correction of blackbody radiation shift in an optical lattice clock.Phys

    Thomas Middelmann, Stephan Falke, Christian Lisdat, and Uwe Sterr. High accuracy correction of blackbody radiation shift in an optical lattice clock.Phys. Rev. Lett., 109:263004, Dec 2012

    work page 2012

Show all 42 references
  1. [9]

    Yt- terbium in quantum gases and atomic clocks: van der Waals interactions and blackbody shifts

    MS Safronova, SG Porsev, and Charles W Clark. Yt- terbium in quantum gases and atomic clocks: van der Waals interactions and blackbody shifts. Phys. Rev. Lett., 109(23):230802, 2012

    2012

  2. [10]

    Beloy, J

    K. Beloy, J. A. Sherman, N. D. Lemke, N. Hinkley, C. W. Oates, and A. D. Ludlow. Determination of the 5d6s 3D1 state lifetime and blackbody-radiation clock shift in Yb. Phys. Rev. A , 86:051404, Nov 2012

    2012

  3. [11]

    Blackbody-radiation shift in the sr optical atomic clock

    MS Safronova, SG Porsev, UI Safronova, MG Kozlov, and Charles W Clark. Blackbody-radiation shift in the sr optical atomic clock. Physical Review A—Atomic, Molec- ular, and Optical Physics , 87(1):012509, 2013

    2013

  4. [12]

    Lisdat, S

    Ch. Lisdat, S. D¨ orscher, I. Nosske, and U. Sterr. Black- body radiation shift in strontium lattice clocks revisited. Phys. Rev. Res. , 3:L042036, Dec 2021

    2021

  5. [13]

    Evaluation of the black- body radiation shift of an yb optical lattice clock at kriss

    Myoung-Sun Heo, Huidong Kim, Dai-Hyuk Yu, Won- Kyu Lee, and Chang Yong Park. Evaluation of the black- body radiation shift of an yb optical lattice clock at kriss. Metrologia, 59(5):055002, 2022

    2022

  6. [14]

    Cryogenic optical lattice clocks

    Ichiro Ushijima, Masao Takamoto, Manoj Das, Takuya Ohkubo, and Hidetoshi Katori. Cryogenic optical lattice clocks. Nat. Photon. , 9:185–189, 2015

    2015

  7. [15]

    Frequency ratios of Sr, Yb, and Hg based optical lattice clocks and their applica- tions

    Masao Takamoto, Ichiro Ushijima, Manoj Das, Nils Ne- mitz, Takuya Ohkubo, Kazuhiro Yamanaka, Noriaki Ohmae, Tetsushi Takano, Tomoya Akatsuka, Atsushi Ya- maguchi, and Hidetoshi Katori. Frequency ratios of Sr, Yb, and Hg based optical lattice clocks and their applica- tions. Co...

    2015

  8. [16]

    A cryogenic strontium lattice clock

    Roman Schwarz. A cryogenic strontium lattice clock . PhD thesis, Gottfried Wilhelm Leibniz Universit¨ at, 2022

    2022

  9. [17]

    Lakeshore pro- vides the negative-temperature-coefficient RTDs (Cernox CX-1080-SD-HT) whose calibrations are NIST-traceable

    The closed cycle cryocooler is a custom split-flow de- sign based on the ColdEdge Stinger, specified at an es- timated cooling power of 5 W at 50 K. Lakeshore pro- vides the negative-temperature-coefficient RTDs (Cernox CX-1080-SD-HT) whose calibrations are NIST-traceable. The...

  10. [18]

    See the Supplemental Material for additional details about the shield, its operation, and the BBR shift evalu- ation and uncertainty analysis

  11. [19]

    Brand et al

    W. Brand et al. Uncertainty and reproducibility evalua- tion of a tranportable Yb optical lattice clock. In Prepa- ration, 2025

    2025

  12. [20]

    High-accuracy measurement of atomic polarizability in an optical lattice clock

    Jeffrey A Sherman, Nathan D Lemke, Nathan Hinkley, Marco Pizzocaro, Richard W Fox, Andrew D Ludlow, and Christopher W Oates. High-accuracy measurement of atomic polarizability in an optical lattice clock. Phys. Rev. Lett., 108(15):153002, 2012

    2012

  13. [21]

    Siegel et al

    J.L. Siegel et al. Comparison of three optical lattice clocks at ≤ 4 × 10−18 agreement. In Preparation, 2025

    2025

  14. [22]

    For these points, we assigned the floor level as the uncer- tainty

    Three data points reached the noise floor at ∼ 5 × 10−18. For these points, we assigned the floor level as the uncer- tainty

  15. [23]

    [9] is the sum νdyn,6 + νdyn,8 = −22.900(800) mHz

    The value reported in Ref. [9] is the sum νdyn,6 + νdyn,8 = −22.900(800) mHz. We subtract νdyn,8 = −0.744(20) mHz in Ref. [10] to yield the displayed value νdyn,6 = −22.156(800). The error on the displayed value is minimally affected by the subtraction, and thus its independen...

  16. [24]

    Demonstration of 4.8×10−17 stability at 7 1 s for two independent optical clocks

    E Oelker, RB Hutson, CJ Kennedy, L Sonderhouse, T Bothwell, A Goban, D Kedar, C Sanner, JM Robinson, GE Marti, et al. Demonstration of 4.8×10−17 stability at 7 1 s for two independent optical clocks. Nature Photonics, 13(10):714–719, 2019

    2019

  17. [25]

    higher- order

    K. Beloy, X. Zhang, W. F. McGrew, N. Hinkley, T. H. Yoon, D. Nicolodi, R. J. Fasano, S. A. Sch¨ affer, R. C. Brown, and A. D. Ludlow. Faraday-shielded dc Stark-shift-free optical lattice clock. Phys. Rev. Lett. , 120:183201, May 2018. 8 Supplemental Material ESTIMA TING THE BB...

    2012

  18. [26]

    https://www.schott.com/en-us/products/optical-glass-p1000267/ downloads/

    Schott optical glass datasheet collection. https://www.schott.com/en-us/products/optical-glass-p1000267/ downloads/

  19. [27]

    A strontium lattice clock with reduced blackbody radiation shift

    Ali Khalas Anfoos Al-Masoudi. A strontium lattice clock with reduced blackbody radiation shift . PhD thesis, Hannover: Gottfried Wilhelm Leibniz Universit¨ at Hannover, 2016

    2016

  20. [28]

    Experimental study on glass and polymers: Determining the optimal material for potential use in terahertz technology

    Md Saiful Islam, Cristiano MB Cordeiro, Md J Nine, Jakeya Sultana, Alice LS Cruz, Alex Dinovitser, Brian Wai-Him Ng, Heike Ebendorff-Heidepriem, Dusan Losic, and Derek Abbott. Experimental study on glass and polymers: Determining the optimal material for potential use in terah...

    2020

  21. [29]

    Terahertz time-domain spectroscopy for material characterization

    Mira Naftaly and Robert E Miles. Terahertz time-domain spectroscopy for material characterization. Proceedings of the IEEE, 95(8):1658–1665, 2007

    2007

  22. [30]

    High-accuracy emissivity data on the coatings nextel 811-21, herberts 1534, aeroglaze z306 and acktar fractal black

    A Adibekyan, E Kononogova, C Monte, and J Hollandt. High-accuracy emissivity data on the coatings nextel 811-21, herberts 1534, aeroglaze z306 and acktar fractal black. International Journal of Thermophysics , 38:1–14, 2017. Coating used in the shield is fractal black. Specifi...

    2017

  23. [31]

    Lakeshore provides the negative-temperature-coefficient RTDs (Cernox CX-1080-SD-HT) whose calibrations are NIST-traceable

    The closed-cycle cryocooler is a custom split-flow design based on the ColdEdge Stinger, specified at an estimated cooling power of 5 W at 50 K. Lakeshore provides the negative-temperature-coefficient RTDs (Cernox CX-1080-SD-HT) whose calibrations are NIST-traceable. The RTDs ...

  24. [32]

    Experimental techniques for low-temperature measurements: cryostat design, material properties and supercon- ductor critical-current testing

    Jack Ekin. Experimental techniques for low-temperature measurements: cryostat design, material properties and supercon- ductor critical-current testing . Oxford university press, 2006

    2006

  25. [33]

    Thermal anchoring of wires in cryogenic apparatus

    JG Hust. Thermal anchoring of wires in cryogenic apparatus. Review of Scientific Instruments , 41(5):622–624, 1970

    1970

  26. [34]

    Farley and William H

    John W. Farley and William H. Wing. Accurate calculation of dynamic Stark shifts and depopulation rates of Rydberg energy levels induced by blackbody radiation. Hydrogen, helium, and alkali-metal atoms. Phys. Rev. A , 23:2397–2424, May 1981

    1981

  27. [35]

    Porsev and Andrei Derevianko

    Sergey G. Porsev and Andrei Derevianko. Multipolar theory of blackbody radiation shift of atomic energy levels and its implications for optical lattice clocks. Phys. Rev. A , 74:020502, Aug 2006. 21

    2006

  28. [36]

    Hunt, Jacob L

    Tobias Bothwell, Benjamin D. Hunt, Jacob L. Siegel, Youssef S. Hassan, Tanner Grogan, Takumi Kobayashi, Kurt Gibble, Sergey G. Porsev, Marianna S. Safronova, Roger C. Brown, Kyle Beloy, and Andrew D. Ludlow. Lattice light shift evaluations in a dual-ensemble Yb optical lattice...

  29. [37]

    Observation and cancellation of a perturbing dc stark shift in strontium optical lattice clocks

    J´ erˆ ome Lodewyck, Michal Zawada, Luca Lorini, Mikhail Gurov, and Pierre Lemonde. Observation and cancellation of a perturbing dc stark shift in strontium optical lattice clocks. IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 59(3):411–415, 2012

    2012

  30. [38]

    J. L. Siegel, W. F. McGrew, Y. S. Hassan, C.-C. Chen, K. Beloy, T. Grogan, X. Zhang, and A. D. Ludlow. Excited-band coherent delocalization for improved optical lattice clock performance. Phys. Rev. Lett. , 132:133201, Mar 2024

    2024

  31. [39]

    Ratchet loading and multi-ensemble operation in an optical lattice clock

    Youssef S Hassan, Takumi Kobayashi, Tobias Bothwell, Jacob L Seigel, Benjamin D Hunt, Kyle Beloy, Kurt Gibble, Tanner Grogan, and Andrew D Ludlow. Ratchet loading and multi-ensemble operation in an optical lattice clock. Quantum Sci. Tech., 9(4):045023, aug 2024

    2024

  32. [40]

    Heat capacity of reference materials: Cu and w

    Guy Kendall White and SJ Collocott. Heat capacity of reference materials: Cu and w. Journal of physical and chemical reference data, 13(4):1251–1257, 1984

    1984

  33. [41]

    Systematic evaluation of an atomic clock at 2 × 10- 18 total uncertainty

    Travis L Nicholson, SL Campbell, RB Hutson, G Edward Marti, BJ Bloom, Rees L McNally, Wei Zhang, MD Barrett, Marianna S Safronova, GF Strouse, et al. Systematic evaluation of an atomic clock at 2 × 10- 18 total uncertainty. Nature communications, 6(1):1–8, 2015

    2015

  34. [42]

    Deter- mination of the 5d 6s3D1 state lifetime and blackbody-radiation clock shift in Yb

    Kyle Beloy, Jeffrey A Sherman, Nathan D Lemke, Nathan Hinkley, Christopher W Oates, and Andrew D Ludlow. Deter- mination of the 5d 6s3D1 state lifetime and blackbody-radiation clock shift in Yb. Physical Review A—Atomic, Molecular, and Optical Physics , 86(5):051404, 2012

    2012

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.