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REVIEW 3 major objections 5 minor 61 references

Large anomalous shifts of potassium-39 Feshbach resonances

T0 review · 3 major / 5 minor · reviewed 2026-08-08 · deepseek-v4-flash

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Pith's one-line read Potassium-39 Feshbach resonances shift by up to 7.5 G under 1063.9 nm optical dipole trap light, the authors show, because the weakly bound Feshbach molecule has a surprisingly large dynamic polarizability at the trap wavelength.

desk verdict A convincing measurement of large ODT-depth-dependent Feshbach shifts in 39K, with the headline polarizability magnitude softer than the quoted errors suggest because it depends on an unpublished differential magnetic moment. read the letter →

arxiv 2608.05512 v1 pith:WIFNI7K6 submitted 2026-08-06 physics.atom-ph cond-mat.quant-gasquant-ph

Ali Zaheer , Mohammed Bouras , Krzysztof Giergiel , Rudolf Grimm , Andrei Sidorov , Peter Hannaford This is my paper · ORCID
classification physics.atom-phcond-mat.quant-gasquant-ph
keywords Feshbachresonancespotassium-39opticaldipoletrapacStarkshiftdynamicpolarizabilitymoleculesultracoldatomsmolecularspectroscopy
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 that two Feshbach resonances in potassium-39, the workhorse 33.6 G resonance and the mixed-spin 39.9 G resonance, move to higher magnetic field by up to 7.5 G when the atoms sit in a 1063.9 nm optical dipole trap, with the shift scaling with trap depth and vanishing as the trap is turned off. The authors argue that the shift is a differential ac Stark shift caused by the weakly bound Feshbach molecule having a surprisingly large dynamic polarizability at the trap wavelength, about four to seven times the sum of the two atomic polarizabilities, and negative for the 33.6 G resonance. They trace the enhancement to a near-coincidence between the 1063.9 nm trap frequency and a transition from the last vibrational level of the metastable a3Σ+u potential to a level of the b3Σ+g potential of K2. If correct, the result means that weakly bound molecules do not always inherit the sum of atomic polarizabilities, with practical consequences for any experiment that tunes the 33.6 G resonance inside an optical trap.

What carries the argument

The engine of the argument is the relation δµ ∆B = (δα/αat) Uav + ∆Uth, which ties the resonance shift ∆B to the differential polarizability δα = 2αat − αmol between the atom pair and the molecule, the differential magnetic moment δµ, and the trap-averaged ac Stark shift Uav. The experiment controls Uav by varying the 1063.9 nm trap power while keeping temperature roughly fixed, and the thermal term is subtracted using a truncated-Boltzmann model of the trapped cloud. The unusually large αmol is then explained by a near-degeneracy: the trap-laser frequency 281.7665 THz lies within roughly 50 GHz of the a3Σ+u(v''=26) → b3Σ+g(v'=4) molecular transition, whose Franck–Condon overlap is large, so the dynamic polarizability is dominated by a nearby molecular resonance and can exceed, even reverse sign relative to, the sum of the atomic polarizabilities.

What would settle it

Measure the shift of the 33.6 G resonance while tuning the single-frequency trap laser across 1063–1066 nm: if the shift does not trace a dispersion-shaped polarizability curve with a sign change and a magnitude that grows toward the molecular resonance, the near-coincidence explanation is wrong. Alternatively, measure δµ of the R1 molecular state by two-photon or radio-frequency association spectroscopy in zero light; if it comes out at −1.9 μB rather than −2.5 μB, the extracted αmol for the 33.6 G resonance drops by 25–30% and the 'four to seven times' claim is overstated.

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Extended reading notes

Core claim

The central claim is that the positions of the potassium-39 Feshbach resonances at 33.6 G and 39.9 G shift by as much as +7.5 G in a 1063.9 nm optical dipole trap, and that this shift is not a temperature effect but a differential ac Stark shift between the incoming atom pair and the quasi-bound Feshbach molecule. From the measured shift versus trap-averaged Stark shift, the paper extracts molecular polarizabilities αmol = −12.5(1.6) αat for the 33.6 G resonance and αmol = +9(1) αat for the 39.9 G resonance at 281.7665 THz, with smaller magnitudes at a frequency shifted by +13.1 GHz. The magnitude is four to seven times the usual sum-of-atoms value for weakly bound Feshbach molecules, and the negative sign for the 33.6 G resonance is the signature of a resonance on the blue-detuned side of a molecular transition. The paper attributes the enhancement to a near-coincidence between the trap-laser frequency and the a3Σ+u (v''=26) → b3Σ+g (v'=4) transition of the K2 molecule, so that the trap light sits within about 50 GHz of the molecular resonance.

Load-bearing premise

The extracted polarizabilities depend on the differential magnetic moment δµ = −2.5 μB for the 33.6 G resonance taken from the authors' own unpublished coupled-channel calculations; if the earlier literature value −1.9 μB is used instead, the extracted molecular polarizability for that resonance changes by roughly 25–30%.

Editorial extensions

If this is right

  • Any 39K experiment that tunes the 33.6 G or 39.9 G resonance inside a 1064 nm optical dipole trap must account for a depth-dependent shift of up to several gauss, which is larger than naive temperature-shift estimates by more than an order of magnitude.
  • The 33.6 G resonance, widely used for creating 39K Bose–Einstein condensates, is only usable at its nominal position in very shallow traps or when the trap light is frequency-tuned away from the molecular resonance.
  • The extracted polarizabilities imply that the trap light can resonantly drive a3Σ+u → b3Σ+g transitions in the Feshbach molecules, so the trap itself acts as a near-resonant molecular light source.
  • Because the 33.6 G resonance has negative molecular polarizability, increasing trap depth pushes the resonance upward in field; the sign and size of this shift can serve as a direct diagnostic of the molecular-state character of a resonance.
  • The dependence of the shift on ODT laser frequency, observed as a decrease for R1 when the laser is shifted by +13.1 GHz, confirms that the enhancement is frequency-selective rather than a generic property of all Feshbach molecules.

Reading between the lines

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

  • If the near-resonance interpretation is right, the same 1064 nm trap should produce large, controllable Feshbach resonance shifts in other alkali species whose triplet transitions fall near common fiber-laser wavelengths; the fact that only two of eight 39K resonances show the effect is then a selection rule sensitive to the hyperfine symmetry of the molecular state.
  • The paper's quantitative extraction leans on a differential magnetic moment taken from its own coupled-channel calculation; redoing the extraction with an independently measured δµ, for example from radio-frequency association spectroscopy, would settle whether the 'four to seven times' enhancement is as large as claimed or partly an artifact of the magnetic-moment input.
  • A direct test would be to tune a single-frequency fiber laser across the a3Σ+u(v''=26) → b3Σ+g(v'=4) region near 1063.9 nm while monitoring the 33.6 G shift; a dispersion-shaped polarizability curve with a zero crossing would map the molecular resonance and would also locate the magic frequency where the trap no longer shifts the resonance.
  • The existence of a negative molecular polarizability for the 33.6 G Feshbach molecule suggests that a suitably blue-detuned trap could cancel the atomic polarizability, potentially creating a state-dependent optical lattice for selectively trapping molecules over atoms.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 5 minor

Summary. The paper reports that two 39K Feshbach resonances, at 33.6 G and 39.9 G, shift by up to +7.5 G in a 1063.9 nm optical dipole trap, while six other studied resonances show essentially no shift. The shifts scale with trap depth, approach zero at zero depth, and persist in a spin-polarized sample at fixed temperature; a second ODT laser frequency changes the shifts. The authors attribute the effect to a differential ac Stark shift caused by anomalously large dynamic polarizabilities of the associated Feshbach molecules. Using Eq. (5) of the appendix, they extract molecular polarizabilities αmol/αat of −12.5(1.6) and +9(1) at 281.7665 THz and interpret these as evidence for near-resonant a3Σ+u → b3Σ+g transitions near the ODT wavelength.

Significance. If the quantitative extraction holds, this is a striking result: it contradicts the usual assumption that weakly bound Feshbach molecules have polarizabilities close to the sum of the two atomic polarizabilities, and it has practical consequences for experiments using the 33.6 G resonance in 1063.9 nm ODTs, including compact BEC machines. The paper's observational case is strong: the zero-depth extrapolation, the fixed-temperature dataset in Fig. 6, the six unshifted resonances in Table II, and the two-frequency comparison are all in the right direction and are explicitly presented. The data are publicly available. The main weakness is that the quantitative polarizability values depend on differential magnetic moments δµ taken from unpublished coupled-channel calculations, with only statistical errors quoted in Table II; this limits the precision, but not the qualitative existence, of the claimed anomaly.

major comments (3)
  1. [Appendix Eq. (5); Table I; Table II] The extracted polarizabilities inherit an unquantified systematic uncertainty from the differential magnetic moments δµ, and Table II quotes only statistical errors. For R1, Table I lists δµ = −2.5 μB from the authors' own coupled-channel calculations [42], while the published value from ref. [5] is −1.9 μB; the paper itself states in Sec. II that the slope of the apparent linear region can lead to systematic error for this resonance. Re-evaluating Eq. (5) with δµ = −1.9 μB changes αmol/αat from −12.5(1.6) to roughly −9.1, a ~27% change. The qualitative anomaly survives, but the abstract's 'four to seven times' statement, the asymmetry between R1 and R3, and the detunings inferred in Sec. V all shift. For R3, δµ = +1.2 μB is also from [tw] with no independent published check. The authors should either propagate a defensible systematic uncertainty for δµ, compare explicitly with published values, or restate the quantitative claims with appropriate caveats.
  2. [Sec. V; Table II] The inferred near-resonant detunings of about +40 GHz and +50 GHz for the two ODT frequencies rest on a single dispersion-shaped line with an assumed natural linewidth of twice the atomic linewidth, and only two frequency points are available. The observed R3 behavior (a small decrease in αmol when the frequency is increased by 13.1 GHz) is not consistent with the simple red-detuned dispersion picture and is attributed to unspecified residual structure. This part of the interpretation should be presented as a model-dependent estimate rather than a determined quantity, or supported by additional frequency points or a calculated line shape.
  3. [Appendix; Fig. 9] The extraction via Eq. (5) uses Uav derived from a spherically symmetric 3D Gaussian trap model with a truncated Boltzmann distribution, whereas the actual crossed ODT is formed by two beams with different waists crossing at 70° and has measured anisotropic trap frequencies. A systematic error in Uav maps directly onto αmol/αat. The authors should quantify how sensitive the extracted polarizabilities are to this modeling choice, either by using the measured trap geometry or by varying the assumed density distribution.
minor comments (5)
  1. [Sec. IV B] There is a typo: 'esentially' should be 'essentially'.
  2. [Fig. 10] The axis labels appear garbled ('Temp averaged (μK)' and 'Trap Depth, /g80K'); the temperature versus trap-depth relation should be labeled clearly.
  3. [Table II] The R6 row reports a shift of +4 mG/µK and αmol/αat = 1.8 without uncertainties, inconsistent with the stated one-standard-error convention for all other rows; also, the R2 row gives αmol/αat = +10(4) despite a shift of +2(7) mG/µK, and no δµ is listed for R2 or R4, so the reader cannot reproduce those entries from Eq. (5).
  4. [Abstract and Sec. VI] The phrase 'four to seven times the sum of the polarizabilities of the two incoming potassium-39 atoms' is slightly indirect: the Table II values are quoted relative to a single atom, so the factors relative to the two-atom sum are −6.25 and +4.5 for R1 and R3. The wording should be made unambiguous.
  5. [References] Reference [29] has inconsistent quotation marks and should be reformatted; reference [60] should be cited in the text rather than appearing only as a URL in the data availability statement.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the measured resonance shifts are independent observables, and the polarizability extraction via Eq. (5) is a standard algebraic relation rather than a fit that reproduces its own input.

full rationale

The paper's central chain is: measure Feshbach-resonance positions versus trap depth; extrapolate to zero depth to confirm known zero-light positions; extract molecular polarizabilities from the slopes using Appendix Eq. (5). None of these steps reduces to its own input. Eq. (5), αmol/αat = 2 + δµ⟨ΔB⟩/Uav − (3/2)kBT/Uav, follows algebraically from the first-order differential ac Stark relation Eq. (3); the slope ⟨ΔB⟩/Uav is an independently measured observable, not a parameter fitted to αmol. The zero-depth intercepts agree with established resonance positions, and the dataset includes six resonances with near-zero shifts and two large shifts of opposite sign, so the extracted enhancement is not forced by the fitting procedure. The main quantitative vulnerability is the differential magnetic moment δµ: Table I lists δµ = −2.5 μB for R1 as '[tw]', from unpublished coupled-channel calculations [42], whereas ref. [5] gives −1.9 μB, and Section II explicitly warns that 'for the broad, intermediate-strength resonance R1, the slope of the apparent linear region can lead to systematic error in the measured molecular magnetic moment at the Feshbach resonance center'. Re-evaluating Eq. (5) with δµ = −1.9 μB would change αmol/αat for R1 from −12.5(1.6) to roughly −9, altering but not erasing the anomaly. This is a genuine systematic-uncertainty and reproducibility concern, and the paper itself flags it, but it is not circularity: the input is not defined in terms of the extracted quantity, and no fit or self-citation chain forces the conclusion. The cited atomic polarizability [43–45] and molecular potentials [46,54] are external inputs; private communications [42,54] are identified as such rather than presented as independent theorems. The paper thus contains no self-definitional, fitted-input-as-prediction, or self-citation-load-bearing step, and the derivation chain is self-contained against external benchmarks.

Assumptions & free parameters 2 free parameters · 7 assumptions · 0 invented entities

The quantitative extraction of molecular polarizabilities is not self-contained: it relies on unpublished coupled-channel δµ values, a simplified spherical trap model, an assumed thermal correction, and an unpublished b3Σ+g potential. These are the main items the reader does not pay for upstream.

free parameters (2)
  • Temperature vs trap depth fit parameters A and B = A=4.45, B=0.0340
    Fit to measured cloud temperature vs ODT depth (Fig 10), used to compute Uav in the extraction model.
  • Assumed molecular transition linewidth = 12 MHz (two times the 6 MHz atomic linewidth)
    Chosen by hand for the dispersion-shape analysis that converts the measured αmol change into detunings of about +40 and +50 GHz; not measured.
assumptions (7)
  • domain assumption The Feshbach resonance shift is linearly related to the differential ac Stark shift via δµ∆B = (δα/αat) Uat + ∆Uth (Appendix Eq 3).
    This is a standard first-order result for Feshbach resonances in an optical field, used without derivation in the paper; it assumes the resonance shift is small and the molecular polarizability is evaluated at the laser frequency.
  • domain assumption The spatially averaged trap potential Uav is computed assuming a spherically symmetric 3D Gaussian trap and a truncated Boltzmann distribution (Appendix Eq 4, Fig 9).
    The actual crossed-beam trap is anisotropic (frequencies 121, 511, 523 Hz), so the spherical assumption is an approximation that affects the conversion from measured slope to αmol.
  • domain assumption The thermal energy difference between the atomic pair and the Feshbach molecule is ⟨∆Uth⟩ = (3/2) kBT (Appendix, near Eq 5).
    The molecule and atoms are assumed to have the same temperature and the kinetic energy contribution enters with the same equipartition value; no independent test is provided.
  • domain assumption The adopted b3Σ+g potential (Orsay group, private communication) is the correct one for assigning the near-resonant transition.
    Published potentials disagree by thousands of cm−1 in dissociation energy (Sec V); the paper selects the private Orsay potential because it agrees with Magnier et al. [52], but this choice is not independently verified.
  • domain assumption The ODT frequency is near the a3Σ+u (v''=26) → b3Σ+g (v'=4) transition, inferred from the 1095-1096 nm bandhead and vibrational spacing.
    The identification of the specific v' level is based on approximate Franck-Condon arguments and limited upper-state data; the paper calls the specific assignment 'likely'.
  • domain assumption The molecular polarizability is dominated by the parallel component α‖ from 3Σ+u → 3Σ+g transitions; the perpendicular contribution from a→b3Πg at 721 nm is negligible.
    This ignores possible perpendicular contributions and assumes the ODT frequency is far from the 721 nm perpendicular transition.
  • domain assumption The coupled-channel calculations of Simoni (private communication) provide accurate resonance positions and differential magnetic moments δµ.
    The extraction of αmol in Eq (5) uses these δµ values; they are not yet published in a peer-reviewed source.

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Cite this review

Pith. "Pith review of Large anomalous shifts of potassium-39 Feshbach resonances." pith.science (2026). https://pith.science/paper/WIFNI7K6

@misc{pith2026260805512,
  author       = {Pith},
  title        = {Pith review of: Large anomalous shifts of potassium-39 Feshbach resonances},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/WIFNI7K6}},
  note         = {Machine review of arXiv:2608.05512}
}
read the original abstract

We report the observation of large anomalous shifts, up to +7.5 G, of the positions of the 33.6 G and 39.9 G Feshbach resonances in potassium-39 atoms confined in a 1063.9 nm optical dipole trap (ODT) at temperatures up to around 35 {\mu}K and trap depths up to about 136 {\mu}K. When the atom cloud is cooled to lower temperatures, by reducing the trap depth of the ODT, the shifts decrease proportionally with trap depth and approach zero at zero depth. We show that the large observed shifts originate from a large differential ac Stark shift between the incoming pair of potassium-39 atoms and the weakly bound Feshbach molecule, which in turn originates from an unexpectedly large dynamic polarizability of the Feshbach molecule. The polarizabilities of the Feshbach molecules extracted from the measured shifts of the 33.6 G and 39.9 G resonances are about four to seven times the sum of the polarizabilities of the two incoming potassium-39 atoms, that is, about four to seven times larger than the usual polarizability of weakly bound Feshbach molecules. The large polarizabilities of the Feshbach molecules are attributed to a near-coincidence between the frequency of the 1063.9 nm ODT laser and the frequency of a molecular transition from the last vibrational level of the lowest triplet a3{\Sigma}+u potential to a vibrational level of the excited b3{\Sigma}+g potential. Other potassium-39 Feshbach resonances we have studied exhibit a zero or very small shift, corresponding to molecular polarizabilities close to the sum of the polarizabilities of the two incoming potassium-39 atoms.

Figures

Figures reproduced from arXiv: 2608.05512 by the authors.

Figure 1
Figure 1. FIG. 1. Calculated [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Calculated partial molecular and atom-pair Zeeman e [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. Scan of the Feshbach atom-loss resonances up to 65 G [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: FIG. 4. (a)-(e) Scans of the R1, R2 and R3 Feshbach atom-loss r [PITH_FULL_IMAGE:figures/full_fig_p006_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. Fine-step scans of the narrow 25.9 G (R0) Feshbach ato [PITH_FULL_IMAGE:figures/full_fig_p007_5.png]
Figure 6
Figure 6. Figure 6: FIG. 6. Measured center position of the R1 33.6 G Feshbach [PITH_FULL_IMAGE:figures/full_fig_p008_6.png]
Figure 7
Figure 7. Figure 7: FIG. 7. Dependence of measured center positions of the stud [PITH_FULL_IMAGE:figures/full_fig_p008_7.png]
Figure 8
Figure 8. Figure 8: FIG. 8. Calculated interaction potentials for the triplet [PITH_FULL_IMAGE:figures/full_fig_p010_8.png]
Figure 9
Figure 9. Figure 9: FIG. 9. Calculated spatially averaged optical dipole trap p [PITH_FULL_IMAGE:figures/full_fig_p011_9.png]
Figure 10
Figure 10. Figure 10: FIG. 10. Dependence of temperature of the trapped [PITH_FULL_IMAGE:figures/full_fig_p012_10.png]

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Works this paper leans on

61 extracted references · 58 canonical work pages

  1. [42]

    Simoni, private communication (2026)

    A. Simoni, private communication (2026)

    work page 2026

  2. [5]

    involving the use of optimized adiabatic Born- Oppenheimer singlet X 1Σ+ g and triplet a3Σ+ u interaction potentials determined from spectroscopic data [ 40, 41] is employed to calculate K 2 interatomic potentials for the molecular states associated with the Feshbach resonances 3 [42]. The interaction potentials at large internuclear sep- arations are par...

    work page

  3. [1]

    H. Wang, P. L. Gould, and W. C. Stwalley, Pho- toassociative spectroscopy of ultracold 39K atoms in a high-density vapor-cell magneto-optical trap, Phys. Rev. A 53, R1216 (1996)

    work page 1996

  4. [2]

    F. S. Cataliotti, E. A. Cornell, C. Fort, M. Inguscio, F. Marin, M. Prevedelli, L. Ricci, and G. M. Tino, Magneto-optical trapping of fermionic potassium atoms, Phys. Rev. A 57, 1136 (1998)

    work page 1998

  5. [3]

    DeMarco and D

    B. DeMarco and D. S. Jin, Onset of Fermi degeneracy in a trapped atomic gas, Science 285, 1703 (1999)

    work page 1999

  6. [4]

    Roati, M

    G. Roati, M. Zaccanti, C. D’Errico, J. Catani, M. Mod- ugno, A. Simoni, M. Inguscio, and G. Modugno, 39K Bose-Einstein condensate with tunable interactions, Phys. Rev. Lett. 99, 010403 (2007)

    work page 2007

  7. [6]

    R. L. D. Campbell, R. P. Smith, N. Tammuz, S. Beattie, S. Moulder, and Z. Hadzibabic, Efficient production of large 39K Bose-Einstein condensates, Phys. Rev. A 82, 063611 (2010)

    work page 2010

  8. [7]

    D’Errico, M

    C. D’Errico, M. Zaccanti, M. Fatorri, G. Roati, M. Ingus- cio, G. Modugno, and A. Simoni, Feshbach resonances in ultracold 39K, New J. Phys. 9, 223 (2007)

    work page 2007

Show all 61 references
  1. [8]

    Marangoni, C

    B. Marangoni, C. Menegatti, and L. Mar- cassa, Loading a 39K crossed optical dipole trap from a magneto-optical trap, J. Phys. B: At. Mol. Opt. Phys. 45, 175301 (2012) . 13

    2012

  2. [9]

    Landini, S

    M. Landini, S. Roy, G. Roati, A. Simoni, M. Ingus- cio, G. Modugno, and M. Fattori, Direct evaporative cooling of 39K atoms to Bose-Einstein condensation, Phys. Rev. A 86, 033421 (2012)

    2012

  3. [10]

    S. Roy, M. Landini, A. Trenkwalder, G. Semeghini, G. Spagnolli, A. Simoni, M. Fattori, M. Inguscio, and G. Modugno, Test of the universality of the three- body Efimov parameter at narrow Feshbach resonances, Phys. Rev. Lett. 111, 053202 (2013)

    2013

  4. [11]

    Salomon, L

    G. Salomon, L. Fouch´ e, P. Wang, A. As- pect, P. Bouyer, and T. Bourdel, Gray-molasses cooling of 39K to a high phase-space density, Europhys. Lett. 104, 053202 (2014)

    2014

  5. [12]

    Salomon, L

    G. Salomon, L. Fouch´ e, S. Lepoutre, A. Aspect, and T. Bourdel, All-optical cooling of 39K to Bose-Einstein condensation, Phys. Rev. A 90, 033405 (2014)

    2014

  6. [13]

    D. Nath, R. K. Easwaran, G. Rajalakshmi, and C. S. Unnikrishnan, Quantum-interference-enhanced deep sub- Doppler cooling of 39K atoms in gray molasses, Phys. Rev. A 88, 053407 (2013)

    2013

  7. [14]

    Culver, A

    R. Culver, A. Lampis, B. Megyeri, K. Pahwa, L. Mu- darikwa, M. Holynski, P. W. Courteille, and J. Goldwin, Collective strong coupling of cold potassium atoms in a ring cavity, New J. Phys. 18, 113043 (2016)

    2016

  8. [15]

    N. B. Jørgensen, L. Wacker, K. T. Skalmstang, M. M. Parish, J. Levinsen, R. S. Christensen, G. M. Bruun, and J. J. Arlt, Observation of attractive and repulsive polarons in a Bose-Einstein condensate, Phys. Rev. Lett. 117, 055302 (2016)

    2016

  9. [16]

    T. A. Schulze, T. Hartmann, K. K. Voges, M. W. Gempel, E. Tiemann, A. Zenesini, and S. Os- pelkaus, Feshbach spectroscopy and dual-species Bose-Einstein condensation of 23Na-39K mixtures, Phys. Rev. A 97, 023623 (2018)

    2018

  10. [17]

    Tanzi, C

    L. Tanzi, C. R. Cabrera, J. Sanz, P. Cheiney, M. Tomza, and L. Tarruell, Feshbach resonances in potassium Bose- Bose mixtures, Phys. Rev. A 98, 062712 (2018)

    2018

  11. [18]

    Y. Wang, S. Shevate, M. Wintermantel, Tobias, M. Mor- gado, G. Lochead, and S. Whitlock, Preparation of hun- dreds of microscopic atomic ensembles in optical tweezer arrays, npj Quantum Inf. 6, 10.1038/s41534-020-0285-1 (2020)

    2020 doi

  12. [19]

    Chapurin, X

    R. Chapurin, X. Xie, M. J. Van de Graaff, J. S. Popowski, J. P. D’Incao, P. S. Julienne, J. Ye, and E. A. Cornell, Precision test of the limits to universality in few-body physics, Phys. Rev. Lett. 123, 233402 (2019)

    2019

  13. [20]

    J.-C. Yu, S. Bhave, L. Reeve, B. Song, and U. Schneider, Observing the two-dimensional Bose glass in an optical quasicrystal, Nature 633, 338–343 (2024)

    2024

  14. [21]

    Herbst, H

    A. Herbst, H. Albers, K. Stolzenberg, S. Bode, and D. Schlippert, Rapid generation of all-optical 39K Bose- Einstein condensates using a low-field Feshbach reso- nance, Phys. Rev. A 106, 043320 (2022)

    2022

  15. [22]

    R. J. Fletcher, M. Robert-de Saint-Vincent, J. Man, N. Navon, R. P. Smith, K. G. H. Viebahn, and Z. Hadz- ibabic, Connecting Berezinskii-Kosterlitz-Thouless and BEC phase transitions by tuning interactions in a trapped gas, Phys. Rev. Lett. 114, 255302 (2015)

    2015

  16. [23]

    Zhang, L

    Y. Zhang, L. Chen, Z. Wang, Y. Wang, P. Wang, L. Huang, Z. Meng, R. Qi, and J. Zhang, Observation of high partial-wave Feshbach resonances in 39K Bose–Einstein condensates, New J. Phys. 27, 063002 (2025)

    2025

  17. [24]

    Petrucciani, A

    T. Petrucciani, A. Santoni, C. Mazzinghi, D. Trypo- georgos, F. S. Cataliotti, M. Inguscio, G. Modugno, A. Smerzi, L. Pezz´ e, and M. Fattori, Mach-Zehnder atom interferometry with non-interacting trapped Bose Einstein condensates, arXiv preprint arXiv:2504.17391 10.48550/arXi...

    2025 doi arXiv

  18. [25]

    R. J. Fletcher, A. L. Gaunt, N. Navon, R. P. Smith, and Z. Hadzibabic, Stability of a unitary Bose gas, Phys. Rev. Lett. 111, 125303 (2013)

    2013

  19. [26]

    Tiemann, P

    E. Tiemann, P. Gersima, K. K. Voges, T. Hart- mann, A. Zenesine, and S. Ospelkaus, Beyond Born- Oppenheimer approximation in ultracold atomic colli- sions, Phys. Rev. Res. 2, 013366 (2020)

    2020

  20. [27]

    Lysebo and L

    M. Lysebo and L. Veseth, Feshbach resonances and tran- sition rates for cold homonuclear collisions between 39K and 41K atoms, Phys. Rev. A 81, 032702 (2010)

    2010

  21. [28]

    Herbst, T

    A. Herbst, T. Estrampes, H. Albers, V. Vollenkem- per, K. Stolzenberg, S. Bode, E. Charron, E. M. Rasel, N. Gaaloul, and D. Schlippert, High-flux source system for matter-wave interferometry exploiting tunable inter- actions, Phys. Rev. Res. 6, 013139 (2024)

    2024

  22. [29]

    C. Chin, R. Grimm, P. Julienne, and E. Tiesinga, Feshbach resonances in ultracold gases, Rev. Mod. Phys. 82, 1225 (2010)

    2010

  23. [30]

    D. M. Bauer, M. Lettner, C. Vo, G. Rempe, and S. D¨ urr, Control of a magnetic Feshbach resonance with laser light, Nat. Phys. 5, 339 (2009)

    2009

  24. [31]

    ”Hammond, ”Collective effects in RF-dressed potassium-39 ultra-cold gases” , Ph.D

    A. ”Hammond, ”Collective effects in RF-dressed potassium-39 ultra-cold gases” , Ph.D. thesis, ”Universit´ e Paris-Saclay” (2023)

    2023

  25. [32]

    Kohstall, M

    C. Kohstall, M. Zaccanti, M. Jag, A. Trenkwalder, P. Massignan, G. M. Bruun, F. Schreck, and R. Grimm, Metastability and coherence of repulsive polarons in a strongly interacting Fermi mixture, Nature 485, 615–618 (2012)

    2012

  26. [33]

    V´ exiau, N

    R. V´ exiau, N. Bouloufa, M. Aymar, J. G. Danzl, M. J. Mark, H.-C. N¨ agerl, and O. Dulieu, Optimal trap- ping wavelengths of Cs 2 molecules in an optical lattice, Eur. Phys. J. D 65, 243 (2011)

    2011

  27. [34]

    P. Peng, R. Zhang, L. Huang, D. Li, Z. Meng, P. Wang, H. Zhai, P. Zhang, and J. Zhang, Universal feature in optical control of a p-wave Feshbach resonance, Phys. Rev. A 97, 012702 (2018)

    2018

  28. [35]

    Cetina, M

    M. Cetina, M. Jag, R. S. Lous, J. T. M. Walraven, R. Grimm, R. S. Christensen, and G. M. Bruun, Deco- herence of impurities in a Fermi sea of ultracold atoms, Phys. Rev. Lett. 115, 135302 (2015)

    2015

  29. [36]

    R. S. Lous, I. Fritsche, M. Jag, F. Lehmann, E. Kir- ilov, B. Huang, and R. Grimm, Probing the interface of a phase-separated state in a repulsive Bose-Fermi mix- ture, Phys. Rev. Lett 120, 243403 (2018)

    2018

  30. [37]

    P. D. Gregory, J. A. Blackmore, J. Aldegunde, J. M. Hutson, and S. L. Cornish, ac Stark ef- fect in ultracold polar 87Rb133Cs molecules, Phys. Rev. A 96, 021402(R) (2017)

    2017

  31. [38]

    S. J. Spence, Assembling single RbCs molecules with op- tical tweezers, PhD Thesis, Durham University (2023)

    2023

  32. [39]

    V. A. Khlebnikov, V. V. Tsyganok, D. A. Pershin, E. T. Davletov, E. Kuznetsova, and A. V. Akimov, Characterizing the temperature dependence of Fano- Feshbach resonances of ultracold polarized thulium, Phys. Rev. A 103, 023306 (2021)

    2021

  33. [40]

    Amiot, J

    C. Amiot, J. Verg` es, and C. Fellows, The long-range pot - ential of the K 2 X 1Σ+ g ground electronic state up to 15 14 ˚ A, J. Chem. Phys. 103, 3350 (1995)

    1995

  34. [41]

    K. Wei, S. Li, R. Wu, Y. Liu, T. Chen, and B. Yan, Observation of an inelastic Feshbach resonance between individual 87Rb and 39K atoms in optical tweezers, Frontiers of Physics 21, 112202 (2026)

    2026

  35. [43]

    G. Zhao, W. T. Zemke, J. T. Kim, B. Ji, H. Wang, J. T. Bahns, W. C. Stwalley, L. Li, A. M. Lyyra, and C. Amiot, New measurements of the a3Σ+ u state of K 2 and improved analysis of long-range disper- sion and exchange interactions between two K atoms, J. Chem. Phys. 105, 7976 (1996)

    1996

  36. [44]

    Ravensbergen, V

    C. Ravensbergen, V. Corre, E. Soave, M. Kreyer, S. Tzanova, E. Kirilov, and R. Grimm, Accurate deter- mination of the dynamical polarizability of dysprosium, Phys. Rev. Lett. 120, 223001 (2018)

    2018

  37. [45]

    M. S. Safronova, U. I. Safronova, and C. W. Clark, Magic wavelengths for optical cooling and trapping of potas- sium, Phys. Rev. A 87, 052504 (2013)

    2013

  38. [46]

    Pashov, P

    A. Pashov, P. Popov, H. Kn¨ ockel, and E. Tiemann, Spec- troscopy of the a3Σ+ u state and the coupling to the X 1Σ+ g state of K 2, Eur. Phys. J. D 46, 241 (2008)

    2008

  39. [47]

    Kiruga, C

    A. Kiruga, C. Cheung, D. Filin, P. Barakhshan, A. Bhosale, V. Badhan, B. Arora, R. Eigen- mann, and M. S. Safronova, Portal for high- precision atomic data and computation, Comput. Phys. Commun. 319, 109951 (2026)

    2026

  40. [48]

    Vadla, R

    C. Vadla, R. Beuc, V. Horvati´ c, M. Movre, A. Quent- meier, and K. Niemax, Comparison of theoretical and experimental red and near infrared absorp- tion spectra in overheated potassium vapour, Eur. Phys. J. D 37, 37 (2006)

    2006

  41. [49]

    Huennekens, S

    J. Huennekens, S. Schaefer, M. Ligare, and W. Happer, Observation of the lowest triplet transitions 3Σ+ u − 3Σ+ g in Na 2 and K 2, J. Chem. Phys. 80, 4794 (1984)

    1984

  42. [50]

    Ligare and J

    M. Ligare and J. B. Edmonds, Recalculation of the in- frared continuum spectrum of the lowest energy triplet transitions in K 2, J. Chem. Phys. 95, 3857 (1991)

    1991

  43. [51]

    R. Beuc, M. Movre, and B. Horvati´ c, Time-efficient numerical simulation of diatomic molecular spectra, Eur. Phys. J. D 68, 59 (2014)

    2014

  44. [52]

    Magnier, M

    S. Magnier, M. Aubert-Fr´ econ, and A. R. Allouche, Theoretical determination of highly excited states of K 2 correlated adiabatically above K(4 p) + (4 p), J. Chem. Phys. 121, 1771 (2004)

    2004

  45. [53]

    Magnier and P

    S. Magnier and P. H. Milli´ e, Potential curves for the ground and numerous highly excited electronic states of K2 and NaK, Phys. Rev. A 54, 204 (1996)

    1996

  46. [54]

    Vexiau, private communication (2026)

    R. Vexiau, private communication (2026)

    2026

  47. [55]

    Yan and W

    L. Yan and W. Meyer, unpublished (2006)

    2006

  48. [56]

    M. Deiß, B. Drews, B. Deissler, and J. H. Denschlag, Probing the axis alignment of an ultracold spin-polarized Rb2 molecule, Phys. Rev. Lett. 113, 233004 (2014)

    2014

  49. [57]

    M. Deiß, B. Drews, J. H. Denschlag, N. Bouloufa-Maafa, R. V´ exiau, and O. Dulieu, Polarizability of ultracold Rb2 molecules in the rovibrational ground state of a3Σ+ u , New J. Phys. 17, 065019 (2015)

    2015

  50. [58]

    V´ exiau, D

    R. V´ exiau, D. Borsalino, M. Lepers, A. Orb´ an, M. Ay- mar, O. Dulieu, and N. Bouloufa-Maafa, Dynamic dipole polarizabilities of heteronuclear alkali dimers: optical response, trapping and control of ultracold molecules, Int. Rev. Phys. Chem. 36, 709 (2017)

    2017

  51. [59]

    J. G. Danzl, M. J. Mark, E. Haller, M. Gustavs- son, R. Hart, J. Aldegunde, J. M. Hutson, and H.- C. N¨ agerl, An ultracold high-density sample of rovi- bronic ground-state molecules in an optical lattice, Nat. Phys. 6, 265 (2010)

    2010

  52. [61]

    [60] https://doi.org/10.25916/SUT.33140294

    ALS, Azur Light Systems (now TOPTICA Photonics SAS), Cit´ e de la Photonique, near Bordeaux, France (2026). [60] https://doi.org/10.25916/SUT.33140294

    2026 doi

  53. [512]

    The temperature of the atom cloud is determined from standard time-of-flight expansion measurements

    operated in kinetics mode. The temperature of the atom cloud is determined from standard time-of-flight expansion measurements. The Feshbach magnetic field is controlled by an analog voltage signal from a National Instruments (NI) card that is fed into a Delta Elektronika (SM 18...

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