Atomic magnetometry based on the ground-state Hanle effect in an elliptically polarized light wave

A.N. Goncharov; A.O. Makarov; D.V. Brazhnikov; K.S. Kozlova

REVIEW 3 major objections 6 minor 77 references

Atomic magnetometry based on the ground-state Hanle effect in an elliptically polarized light wave

T0 review · 3 major / 6 minor · reviewed 2026-08-03 · deepseek-v4-flash

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

Pith's one-line read The paper demonstrates that a single resonant elliptically polarized laser beam through a miniature 85 °C cesium cell can act as a zero-field atomic magnetometer, reaching 180 fT/√Hz under current technical noise and an estimated photon-sho

desk verdict A clean proof-of-principle of a single-beam resonant Hanle magnetometer at 85°C, but the headline 180 fT/√Hz is a 2-kHz photodetector-limited estimate, not a demonstrated low-frequency sensitivity. read the letter →

arxiv 2511.18710 v1 pith:25D3KDMG submitted 2025-11-24 physics.atom-ph quant-ph

D.V. Brazhnikov , A.O. Makarov , K.S. Kozlova , A.N. Goncharov This is my paper · ORCID

classification physics.atom-phquant-ph PACS 07.55.Ge

keywords ground-stateHanleeffectatomicmagnetometerellipticallypolarizedlightbalancedpolarimetrycesiumvaporcellzero-fieldmagnetometryphoton-shot-noiselimitmagnetocardiography

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 authors are trying to establish that a zero-field atomic magnetometer can be built from a single resonant elliptically polarized beam passing through a tiny cesium vapor cell held at only 85 °C, with no need for the spin-exchange relaxation-free (SERF) regime that normally forces cells to 140–200 °C. They observe ground-state Hanle resonances as changes in the transmitted beam's ellipticity, read out by balanced polarimetry that cancels laser intensity noise. With a 0.125 cm3 cell they measure 180 fT/√Hz sensitivity, limited by technical noise, and estimate the photon-shot-noise floor at about 5 fT/√Hz. If correct, this makes high-sensitivity magnetometry available in a low-heat, small sensor head with a 200 Hz bandwidth and relaxed magnetic-shielding demands, which matters for biomedical imaging near the body.

What carries the argument

The central object is the ground-state Hanle resonance produced in an elliptically polarized wave, treated as two independent circular components—a σ+ pump wave and a σ− probe wave—whose optical pumping rates compete. The transmitted intensities follow Lorentzian functions of the Larmor frequency, and the opposite signs of the EIT and EIA resonances enable balanced polarimetry that converts magnetic-field-dependent circular dichroism into a large common-mode-rejected signal. Sensitivity is estimated from δB ≈ Δ/SNR, where Δ is the resonance half-width and SNR is measured at 2 kHz on the resonance slope.

What would settle it

Operate the sensor in a well-shielded, low-noise environment and record the noise spectral density and Allan deviation while applying a known step in a DC magnetic field; if the measured low-frequency sensitivity is worse than 180 fT/√Hz because of 50 Hz harmonics or 1/f noise, the headline figure does not transfer to DC operation. To test the ~5 fT/√Hz projection, increase optical power toward 3 mW and see whether the noise floor follows the photon-shot-noise scaling; a plateau above the projected floor would refute it.

Watch

Extended reading notes

Core claim

The central claim is that the ground-state Hanle effect in an elliptically polarized resonant light wave yields magneto-optical resonances readable as a change in ellipticity, and that balanced detection of the pump and probe circular components gives a signal-to-noise ratio high enough for sub-picotesla sensitivity without SERF. In the experiment, a single beam tuned to the Cs D1 line is decomposed into a σ+ pump and a σ− probe; competition between these two components creates electromagnetically induced transparency and absorption resonances at zero transverse field. The differential signal suppresses laser intensity noise. The authors report a resonance half-width of about 90 nT, a sensor

Load-bearing premise

The quoted sensitivities assume that the signal-to-noise ratio measured at 2 kHz on the resonance slope, combined with the half-width via δB ≈ Δ/SNR, represents the sensor noise floor at all frequencies; the paper's own spectra show strong 50 Hz harmonics and 1/f technical noise below 1.5 kHz, which would degrade real DC or low-frequency operation.

Editorial extensions

If this is right

At the demonstrated 180 fT/√Hz level, the sensor is already adequate for magnetocardiography, which requires detecting roughly 10–100 pT fields.
The absence of the SERF regime allows an 85 °C cell, cutting heat dissipation and letting the sensor head sit closer to a patient's body.
The measured 200 Hz bandwidth can be pushed higher in a closed-loop configuration, and modulation frequencies well above the bandwidth can still produce a high-slope error signal.
A resonance half-width of about 90 nT, several times larger than in SERF sensors, translates into a wider dynamic range and less demanding shielding.
Suppressing the technical noise sources should bring the sensor close to the ~5 fT/√Hz photon-shot-noise floor, comparable to leading miniature zero-field magnetometers.

Reading between the lines

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

A direct test the authors did not perform is low-frequency operation: their own noise spectrum shows 50 Hz harmonics and 1/f noise below ~1.5 kHz, so a dedicated low-noise current supply and extra shielding are needed to confirm 180 fT/√Hz in the DC-to-100 Hz band used by biomagnetism.
If the bulk wave plates and Wollaston prism are replaced by a monolithic nanophotonic polarimeter, the same physics could scale to arrays of identical ~1 cm3 sensor heads for full-head magnetoencephalography.
Because the laser is locked to the absorption line center, laser frequency noise is largely suppressed; extending this line-center operation to other alkali transitions could simplify frequency stabilization in field-deployable sensors.

Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

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

Colleague,

This is a workmanlike experimental paper on a zero-field magnetometer using the ground-state Hanle effect in a single elliptically polarized resonant beam through a 0.125 cm3 Cs cell at 85°C. The genuinely new bit is the unmodulated, resonant configuration: instead of the usual detuned elliptically-polarized pump-probe scheme (Shah & Romalis) or their own earlier Bell-Bloom version, they use one resonant wave, detect the ellipticity change via balanced polarimetry, and still get sub-pT noise at 2 kHz. That is worth knowing if you work on miniature OPMs. The paper is honest about its model: the Bloch-equation treatment is explicitly qualitative, with hand-picked parameters, and the measured resonances, power broadening, and bandwidth data are presented clearly. The 200-Hz bandwidth and 85°C operation are useful for biomedical applications if the sensitivity holds at low frequencies.

The main soft spot is exactly where the stress-test lands. The 180 fT/√Hz is derived from a single noise voltage measurement at 2 kHz on the resonance slope, using δB = Δ/SNR. The paper's own Fig. 4(d) shows strong technical noise below 1.5 kHz. The authors argue that modulation-demodulation at 2 kHz moves the carrier above that noise, but that does not remove low-frequency magnetic-field noise: a slowly varying ambient field shifts the operating point and modulates the slope, transferring low-frequency noise into the demodulated output. They do not show a calibrated AC field response at, say, 10 Hz, nor a demodulated noise spectrum. So the 180 fT/√Hz should be read as a photodetector-limited floor at 2 kHz, not a demonstrated DC–100 Hz sensitivity. The 5 fT/√Hz shot-noise estimate is a projection using SNR ≈ √(photon flux), and it ignores atomic projection noise, which at this cell size and temperature could be of the same order. That said, the authors flag that technical noise currently limits them and list mitigations (ferrite shields, gradiometry, low-noise current supplies). The missing low-frequency measurement is a gap, not a fatal flaw.

The citation pattern is fine; the self-citations are to their prior level-crossing work and are appropriate. The paper would benefit from repeated measurements with error bars, a demodulated noise spectrum, and a low-frequency sensitivity measurement before any biomedical claim is taken at face value. For the field, it is a useful incremental contribution. I would send it to a careful referee—preferably someone who will push on the noise transfer question—but I would not desk-reject it.

Recommendation: engage, but treat the headline sensitivity as an upper bound on what has been demonstrated.

Referee Report

3 major / 6 minor

Summary. The manuscript reports a ground-state Hanle effect (GSHE) magnetometry scheme using a single resonant elliptically polarized beam in a miniature Cs vapor cell (≈0.125 cm³, ≈85 °C) with ~200 Torr buffer gas. Magneto-optical resonances are observed as changes in the transmitted ellipticity, detected by balanced polarimetry of the two circular components. The authors report a technical-noise-limited sensitivity of 180 fT/√Hz, a measured sensor bandwidth of 200 Hz, and a projected photon-shot-noise-limited sensitivity of ~5 fT/√Hz. A Bloch-equation model is used to qualitatively explain the resonance line shapes and signs.

Significance. If the sensitivity is confirmed at the frequencies relevant for biomedical applications, the scheme would be a useful addition to miniaturized atomic magnetometry: it avoids the SERF regime, operates at lower cell temperature, and uses a single resonant beam without optical frequency detuning. The balanced polarimetry approach suppresses laser intensity noise, and the authors are transparent about the qualitative nature of their model and the presence of technical noise. The experimental data on resonance width, amplitude, noise spectrum, and modulation response are valuable. The main weakness is that the headline sensitivity is inferred from a noise measurement at 2 kHz, while the intended applications (MCG/MEG) require operation at DC–100 Hz where the authors' own noise spectrum shows strong technical noise.

major comments (3)

[§III, Eq. (8), Fig. 4(d)–4(f)]
[Eq. (8), Fig. 4(e)]
[§III, Fig. 4(f), Refs. [16,72,73]]

minor comments (6)

[Abstract]
[Fig. 1 and §II]
[Fig. 4(d)]
[Eq. (2), §II]
[§II, Appendix]
[References]

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the headline sensitivity is measured, and the model is explicitly qualitative; self-citations are contextual.

full rationale

The paper's central quantitative claim, 180 fT/√Hz, is an experimental result obtained by measuring the resonance half-width and the signal-to-noise ratio at 2 kHz on the resonance slope, then applying the standard magnetometer calibration δB ≈ Δ/SNR (Eq. 8, with Ref. [68]). This is a measurement, not a prediction from the model, and the calibrated SNR is not a fitted parameter. The theoretical Bloch-equation and Beer-Lambert treatment in Section II is explicitly labeled 'intended only as a qualitative explanation of the signals observed in the experiments', and the illustrative parameters (Rc = 3Rp = 3Γ, κL = 0.2) are not fitted to the measured sensitivity. The photon-shot-noise-limited estimate of ~5 fT/√Hz is a clearly labeled projection based on the standard photon-flux relation SNR ≈ √(photon flux), and it is not used to derive the measured performance. Self-citations to the authors' prior work appear in the introduction and discussion as background, e.g., 'We previously utilized a similar configuration to observe MORs using the Bell-Bloom technique [44]', but they are not invoked as proof of the central claim and no uniqueness theorem or ansatz is imported from them. The paper's own limitation—technical 1/f noise and 50-Hz harmonics below ~1.5 kHz, which may not transfer to low-frequency operation—is a validity/applicability concern rather than a circularity in the derivation. No step reduces, by construction, to its own input.

Assumptions & free parameters 4 free parameters · 7 assumptions · 0 invented entities

The central sensitivity claim rests on standard Bloch-equation/Beer-Lambert modeling plus measured linewidth and noise; no new entities are introduced. The model parameters are illustrative, not fitted to the headline sensitivity.

free parameters (4)

Rc = 3Γ (illustrative)
Pump rate ratio chosen for Fig. 2; not fitted to data or to the sensitivity claim.
Rp = Γ (illustrative)
Probe rate ratio chosen for Fig. 2; not fitted to data.
Γ = unit scale
Relaxation rate used as the frequency unit in Fig. 2; not fitted to the measured HWHM.
κL = 0.2
Optical depth used for the illustrative curves in Fig. 2; the experimental optical depth is not reported.

assumptions (7)

domain assumption Bloch equation (3) with a single relaxation rate Γ for transverse and longitudinal components adequately describes the ground-state spin dynamics.
Invoked in Sec. II; the authors explicitly call it a qualitative model and note a rigorous treatment requires the density matrix including birefringence.
domain assumption Light-induced Zeeman coherences are negligible at buffer-gas pressures ≳100 Torr, so the σ+ and σ− components of the elliptical wave act as independent pump and probe.
Sec. II paragraph: 'the effects of such Zeeman coherences are strongly suppressed... allowing the two field components... to be considered as independent.'
domain assumption The medium is optically thin, so Mz does not depend significantly on z and Beer-Lambert integration can use constant Mz.
Sec. II before Eqs. (6)-(7); this is an approximation for a cell with κL=0.2, but the real cell optical depth is not quantified.
domain assumption The magnetic field scan is adiabatic, so steady-state solutions of Eq. (3) apply.
Sec. II: 'Bx is scanned at a certain frequency... adiabatic regime applies... we consider the steady-state regime.'
domain assumption Photon-shot-noise-limited SNR equals the square root of the photon flux.
Sec. III, used to estimate the ~5 fT/√Hz floor; standard result cited to [16,73] but not derived in this paper.
standard math Resonance sign is governed by the Wigner 6j symbol expression (A.7).
Appendix A.7; standard angular-momentum result.
domain assumption Minimum detectable field is given by δB ≈ Δ/SNR (Eq. 8).
Sec. III; standard definition, but assumes the noise is white and the resonance slope is linear.

how reviews work

0 comments

Cite this review

Pith. "Pith review of Atomic magnetometry based on the ground-state Hanle effect in an elliptically polarized light wave." pith.science (2026). https://pith.science/paper/25D3KDMG

@misc{pith2026251118710,
  author       = {Pith},
  title        = {Pith review of: Atomic magnetometry based on the ground-state Hanle effect in an elliptically polarized light wave},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/25D3KDMG}},
  note         = {Machine review of arXiv:2511.18710}
}

abstract

We investigate the ground-state Hanle effect in alkali-metal vapor irradiating by a resonant elliptically polarized light wave. The magneto-optical resonances are observed as a change in the ellipticity parameter of the light wave polarization when scanning the transverse magnetic field near zero. We use a miniature ($\approx\,$$0.125$ cm$^3$) glass cesium vapor cell heated to a relatively low temperature of $\approx\,$$85^\circ$C. Under the current experimental conditions, the sensitivity of magnetic field measurements is limited by a technical noise, reaching $180$ fT/$\surd$Hz in a $200$ Hz bandwidth. The ultimate photon-shot-noise-limited sensitivity of the method is estimated to be $\approx\,$$5$ fT/$\surd$Hz. The proposed scheme is promising for the development of a zero-field atomic magnetometer with reduced heat dissipation of the sensor head and relaxed requirements for magnetic shielding compared to counterparts operating in the spin-exchange relaxation-free regime. These features are of particular value for biomedical applications.

Figures

Figures reproduced from arXiv: 2511.18710 by the authors.

**Figure 2.** FIG. 2. The transmitted intensity of the pump wave (upper [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗

**Figure 3.** FIG. 3. (a) Schematic of the experimental apparatus: ECDL, e [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗

Figures from the paper (3 more)

**Figure 4.** Figure 4: FIG. 4. (a) MOR signals recorded from the three BPD channels a [PITH_FULL_IMAGE:figures/full_fig_p006_4.png]

**Figure 5.** Figure 5: FIG. 5. (a) Resonance slope as a function of the modulation fr [PITH_FULL_IMAGE:figures/full_fig_p007_5.png]

**Figure 6.** Figure 6: FIG. 6. Magneto-optical resonances observed in the cesium v [PITH_FULL_IMAGE:figures/full_fig_p009_6.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

77 extracted references

[1]

J. C. Allred, R. N. Lyman, T. W. Kornack, et al. , High- sensitivity atomic magnetometer unaﬀected by spin- exchange relaxation, Phys. Rev. Lett. 89, 130801 (2002)

2002
[2]

I. K. Kominis, T. W. Kornack, J. C. Allred, et al. , A subfemtotesla multichannel atomic magnetometer, Na- ture 422, 596 (2003)

2003
[3]

Budker and M

D. Budker and M. V. Romalis, Optical magnetometry, Nat. Phys. 3, 227 (2007)

2007
[4]

W. Xiao, C. Sun, L. Shen, et al. , A movable unshielded magnetocardiography system, Sci. Adv. 9, eadg1746 (2023)

2023
[5]

J. Chen, C. Ye, X. Hou, et al. , Bias calibration of opti- cally pumped magnetometers based on variable sensitiv- ity, Sensors 25, 433 (2025)

2025
[6]

Osborne, J

J. Osborne, J. Orton, O. Alem, et al. , Fully integrated standalone zero ﬁeld optically pumped magnetometer for biomagnetism, SPIE Proc. 10548, 105481G (2018)

2018
[7]

E. Boto, V. Shah, R. M. Hill, et al. , Triaxial detection of the neuromagnetic ﬁeld using optically-pumped mag- netometry: feasibility and application in children, Neu- roImage 252, 119027 (2022)

2022
[8]

O. Alem, K. J. Hughes, I. Buard, et al. , An integrated full-head OPM-MEG system based on 128 zero-ﬁeld sen- sors, Front. Neurosci. 17, 1190310 (2023)

2023

Show all 77 references

[9]

Fedosov, D

N. Fedosov, D. Medvedeva, O. Shevtsov, et al. , A reliable and reproducible real-time access to sensorimotor rhythm with a small number of optically pumped magnetometers, J. Neural Eng. 22, 046031 (2025)

2025
[10]

Fabricant, G

A. Fabricant, G. Z. Iwata, S. Scherzer, et al. , Action potentials induce biomagnetic ﬁelds in carnivorous Venus ﬂytrap plants, Sci. Rep. 11, 1438 (2021)

2021
[11]

Taskova, E

E. Taskova, E. Alipieva, S. Kolev, et al. , Coherent opti- cal spectroscopy characterization of the magnetic proper- ties of oriented Fe 3O4 nanoparticles, J. Phys. Conf. Ser. 2240, 012022 (2022)

2022
[12]

Wickenbrock, F

A. Wickenbrock, F. Tricot, and F. Renzoni, Magnetic induction measurements using an all-optical 87Rb atomic magnetometer, Appl. Phys. Lett. 103, 243503 (2013)

2013
[13]

Afach, D

S. Afach, D. Budker, G. DeCampet, et al. , Characteri- zation of the global network of optical magnetometers to search for exotic physics (GNOME), Phys. Dark Universe 22, 162 (2018)

2018
[14]

Ellmeier, C

M. Ellmeier, C. Amtmann, A. Pollinger, et al. , Fre- quency shift compensation for single and dual laser beam pass sensors of a coherent population trapping resonance based coupled dark state magnetometer, Measurement: Sensors 25, 100606 (2023)

2023
[15]

E. B. Aleksandrov and A. K. Vershovskii, Modern radio- optical methods in quantum magnetometry, Phys. Usp. 52, 573 (2009)

2009
[16]

Fabricant, I

A. Fabricant, I. Novikova, and G. Bison, How to build a magnetometer with thermal atomic vapor: a tutorial, New J. Phys. 25, 025001 (2023)

2023
[17]

Gawlik, D

W. Gawlik, D. Gawlik, and H. Walther, in The Hanle Eﬀect and Level-Crossing Spectroscopy, The Hanle Eﬀect and Atomic Physics, G. Moruzzi and F. Strumia, eds. (Springer, New York, 1991) Chapter 2, pp. 47-85

1991
[18]

Breschi and A

E. Breschi and A. Weis, Ground-state Hanle eﬀect based on atomic alignment, Phys. Rev. A 86, 053427 (2012)

2012
[19]

Alipieva, S

E. Alipieva, S. V. Gateva, and E. Taskova, Potential of the single-frequency CPT resonances for magnetic ﬁeld measurement, IEEE Trans. Instrum. Meas. 54(2), 738 (2005)

2005
[20]

V. Shah, S. Knappe, P. D. D. Schwindt, et al. , Sub- picotesla atomic magnetometry with a microfabricated vapour cell, Nat. Photonics 1, 649 (2007)

2007
[21]

Papoyan, S

A. Papoyan, S. Shmavonyan, A. Khanbekyan, et al. , Magnetic-ﬁeld-compensation optical vector magnetome- ter, Appl. Opt. 55(4), 892 (2016)

2016
[22]

Le Gal, G

G. Le Gal, G. Lieb, F. Beato, et al. , Dual-axis Hanle magnetometer based on atomic alignment with a single optical access, Phys. Rev. Applied 12, 064010 (2019)

2019
[23]

H. F. Dong, J. C. Fang, B. Q. Zhou, et al. , Three- dimensional atomic magnetometry, Eur. Phys. J. Appl. Phys. 57, 21004 (2012)

2012
[24]

Azizbekyan, S

H. Azizbekyan, S. Shmavonyan, A. Khanbekyan, et al. , High-speed optical three-axis vector magnetometry based on nonlinear Hanle eﬀect in rubidium vapor, Opt. Eng. 56, 074104 (2017)

2017
[25]

Le Gal and A

G. Le Gal and A. Palacios-Laloy, Zero-ﬁeld magnetome- try based on the combination of atomic orientation and alignment, Phys. Rev. A 105, 043114 (2022)

2022
[26]

Holmes, M

N. Holmes, M. Rea, J. Chalmers, et al. , A lightweight magnetically shielded room with active shielding, Sci. Rep. 12, 13561 (2022)

2022
[27]

Skidchenko, A

E. Skidchenko, A. Butorina, N. Fedosov, et al. , The tale of two rooms: comparison of QuSpin zero-ﬁeld OPMs op- eration in two magnetically shielded environments, IEEE Tran. Instrum. Meas. 74, 9516511 (2025)

2025
[28]

Zhang, Z

Y. Zhang, Z. Wang, L. Cao, et al. , Enhanced gradient ﬁeld compensation in multi-channel atomic magnetome- ters with adaptive algorithms, Adv. Quantum Technol. 8, 2400346 (2025)

2025
[29]

Happer and A

W. Happer and A. C. Tam, Eﬀect of rapid spin ex- change on the magnetic-resonance spectrum of alkali va- pors, Phys. Rev. A 16, 1877 (1977)

1977
[30]

Zhang, J

S. Zhang, J. Lu, Y. Zhou, et al. , Zero ﬁeld optically pumped magnetometer with independent dual-mode op- eration, Chin. Opt. Lett. 20, 081202 (2022)

2022
[31]

Twinleaf

“Twinleaf” LLC, https://twinleaf.com 11
[32]

Shah and M

V. Shah and M. V. Romalis, Spin-exchange relaxation- free magnetometry using elliptically polarized light, Phys. Rev. A 80, 013416 (2009)

2009
[33]

J. Tang, Y. Zhai, L. Cao, et al. , High-sensitivity oper- ation of a single-beam atomic magnetometer for three- axis magnetic ﬁeld measurement, Opt. Express 29, 15641 (2021)

2021
[34]

Sebbag, E

Y. Sebbag, E. Talker, A. Naiman, et al. , Demonstra- tion of an integrated nanophotonic chip-scale alkali vapor magnetometer using inverse design, Light: Science & Ap- plications 10, 54 (2021)

2021
[35]

X. Yang, M. Benelajla, S. Carpenter, et al. , Analysis of atomic magnetometry using metasurface optics for bal- anced polarimetry, Opt. Express 31, 13436 (2023)

2023
[36]

Y. Hu, Z. Hu, X. Liu, et al. , Reduction of far oﬀ- resonance laser frequency drifts based on the second har- monic of electro-optic modulator detection in the opti- cally pumped magnetometer, Appl. Opt. 56(21), 5927 (2017)

2017
[37]

M. V. Petrenko, A. S. Pazgalev, and A. K. Vershovskii, Single-beam all-optical nonzero-ﬁeld magnetometric sen- sor for magnetoencephalography applications, Phys. Rev. Appl. 15, 064072 (2021)

2021
[38]

M. V. Petrenko and A. K. Vershovskii, Anomalous sup- pression of spin-exchange relaxation in alignment signals in cesium in ultraweak magnetic ﬁelds, Phys. Rev. A 112, 013123 (2025)

2025
[39]

Corvilain, V

P. Corvilain, V. Wens, M. Bourguignon, et al. , Pushing the boundaries of MEG based on optically pumped mag- netometers towards early human life, Imaging Neurosci. 3, imag a 00489 (2025)

2025
[40]

S. Wang, J. Lu, K. Zhang, et al. , Zero-ﬁeld atomic mag- netometer to extract longitudinal magnetic ﬁeld, Phys. Rev. Research 7, L032024 (2025)

2025
[41]

M. V. Petrenko, A. S. Pazgalev, and A. K. Ver- shovskii, Ultimate parameters of the all-optical single- beam nonzero magnetic ﬁeld sensor for biological appli- cations, IEEE Mag. Lett. 12, 8104605 (2021)

2021
[42]

L. M. Rushton, L. Elson, A. Meraki, et al. , Alignment- based optically pumped magnetometer using a buﬀer-gas cell, Phys. Rev. Appl. 19, 064047 (2023)

2023
[43]

Bonnet, D

M. Bonnet, D. Schwartz, T. Gutteling, et al., A fully inte- grated whole-head helium OPM MEG: a performance as- sessment compared to cryogenic MEG, Front. Med. Tech- nol. 7, 1548260 (2025)

2025
[44]

Makarov, K

A. Makarov, K. Kozlova, D. Brazhnikov, et al. , All- optical atomic magnetometry using an elliptically po- larized amplitude-modulated light wave, Opt. Commun. 577, 131369 (2025)

2025
[45]

S. P. Krzyzewski, A. R. Perry, V. Gerginov, et al. , Characterization of noise sources in a microfabricated single-beam zero-ﬁeld optically-pumped magnetometer, J. Appl. Phys. 126, 044504 (2019)

2019
[46]

N. Ma, L. Duan, D. Ma, et al. , Demonstration of a high- density alkali-metal atomic magnetometer based on the frequency-symmetrical detuning eﬀect of two pumping lights, Opt. Express 30, 45930 (2022)

2022
[47]

J. Peng, Y. Yin, A.-N. Xu, et al. , Signal-enhanced high- sensitivity atomic magnetometer based on multi-pass cell, Appl. Phys. Express 17, 112003 (2024)

2024
[48]

Johnson, P

C. Johnson, P. D. D. Schwindt, and M. Weisend, Magne- toencephalography with a two-color pump-probe, ﬁber- coupled atomic magnetometer, App. Phys. Lett. 97, 243703 (2010)

2010
[49]

B. Zhao, J. Tang, L. Li, et al. , Femtotesla 87Rb magne- tometer based on a coaxial pump-probe beam delivery system, Sensors & Actuators: A. Physical 364, 114856 (2023)

2023
[50]

D. A. Varshalovich, A. N. Moskalev, and V. K. Kher- sonskii, Quantum Theory of Angular Momentum (World Scientiﬁc Publishing, Singapore, 1988)

1988
[51]

H. G. Dehmelt, Modulation of a light beam by precessing absorbing atoms, Phys. Rev. 105(6), 1924 (1957)

1924
[52]

R. E. Slocum and B. I. Marton, Measurement of weak magnetic ﬁelds using zero-ﬁeld parametric resonance in optically pumped He 4, IEEE Trans. Magnet. MAG- 9(3), 221 (1973)

1973
[53]

I. M. Savukov, S. J. Seltzer, M. V. Romalis, et al. , Tunable atomic magnetometer for detection of radio- frequency magnetic ﬁelds, Phys. Rev. Lett. 95, 063004 (2005)

2005
[54]

D. V. Brazhnikov, V. I. Vishnyakov, A. N. Goncharov, et al., Level-crossing resonances on open atomic transitions in a buﬀered Cs vapor cell: linewidth narrowing, high contrast, and atomic magnetometry applications, Phys. Rev. A 106, 013113 (2022)

2022
[55]

D. V. Brazhnikov, V. I. Vishnyakov, S. M. Ignatovich, et al., High-contrast level-crossing resonances in a small ce- sium vapor cell for applications in atomic magnetometry, Appl. Phys. Lett. 119, 024001 (2021)

2021
[56]

D. V. Brazhnikov, S. M. Ignatovich, A. S. No- vokreshchenov, et al. , Ultrahigh-quality electromagnet- ically induced absorption resonances in a cesium vapor cell, J. Phys. B: At. Mol. Opt. Phys. 52, 215002 (2019)

2019
[57]

Brazhnikov, S

D. Brazhnikov, S. Ignatovich, I. Mesenzova, et al. , Shift of zero-ﬁeld level-crossing resonance in the Cs D 1 line and its use in vector magnetometry, Opt. Lett. 45, 3309 (2020)

2020
[58]

A. O. Makarov, D. V. Brazhnikov, and A. N. Goncharov, Observation of the strong magneto-optical rotation of the polarization of light in rubidium vapor for applications in atomic magnetometry, JETP Lett. 117, 509 (2023)

2023
[59]

Oelsner, V

G. Oelsner, V. Schultze, R. IJsselsteijn, et al. , Perfor- mance analysis of an optically pumped magnetometer in Earth’s magnetic ﬁeld, EPJ Quantum Technology 6(1), 1 (2019)

2019
[60]

Y. Chen, L. Zhao, N. Zhang, et al. , Single beam Cs-Ne SERF atomic magnetometer with the laser power diﬀer- ential method, Opt. Express 30(10), 16541 (2022)

2022
[61]

Y. Ma, Y. Chen, M. Yu, et al. , Ultrasensitive SERF atomic magnetometer with a miniaturized hybrid vapor cell, Microsystems & Nanoengineering 10, 121 (2024)

2024
[62]

Nienhuis and F

G. Nienhuis and F. Schuller, Magneto-optical eﬀects of saturating light for arbitrary ﬁeld direction, Opt. Com- mun. 151, 40 (1998)

1998
[63]

E. N. Popov, V. A. Bobrikova, S. P. Voskoboinikov, et al., Features of the formation of the spin polarization of an alkali metal at the resolution of hyperﬁne sublevels in the 2S1/2 state, JETP Lett. 108, 513 (2018)

2018
[64]

Vitawave

“Vitawave”, https://vitawave.ru
[65]

T. W. Kornack, S. J. Smullin, S.-K. Lee, et al. , A low-noise ferrite magnetic shield, Appl. Phys. Lett. 90, 223501 (2007)

2007
[66]

J. Lu, D. Ma, K. Yang, et al. , Study of magnetic noise of a multi-annular ferrite shield, IEEE Access 8, 40918 (2020)

2020
[67]

Petrenko and A

M. Petrenko and A. Vershovskii, Towards a practical implementation of a single-beam all-optical non-zero- 12 ﬁeld magnetic sensor for magnetoencephalographic com- plexes, Sensors 22, 9862 (2022)

2022
[68]

Jim´ enez-Mart ´ ınez, W

R. Jim´ enez-Mart ´ ınez, W. Clark Griﬃth, Y.-J. Wang, et al. , Sensitivity comparison of Mx and frequency- modulated Bell-Bloom Cs magnetometers in a microfab- ricated cell, IEEE Trans. Instrum. Meas. 59, 372 (2010)

2010
[69]

B. Zhao, J. Tang, L. Li, et al. , Transient dynamics of magneto-optic rotation with elliptically polarized light , Results in Physics 60, 107686 (2024)

2024
[70]

Cohen-Tannoudji, J

C. Cohen-Tannoudji, J. Dupont-Roc, S. Haroche, et al. , Diverses r´ esonances de croisement de niveaux sur des atomes pomp´ es optiquement en champ nul. I. Th´ eorie, Rev. Phys. Appl. (Paris) 5, 95 (1970)

1970
[71]

X. Li, Z. Guo, R. Yang, et al. , Single-beam double- pass miniaturized atomic magnetometer for biomagnetic imaging systems, IEEE Sensors J. 23, 12433 (2023)

2023
[72]

A. K. Vershovskii, S. P. Dmitriev, G. G. Kozlov, et al. , Projection spin noise in optical quantum sensors based on thermal atoms, Tech. Phys. 65, 1193 (2020)

2020
[73]

Budker and M

D. Budker and M. G. Kozlov, Sensing: equation one, Opt. Mem. Neural Networks 32, S409 (2023)

2023
[74]

Klassen, S

W. Klassen, S. Ahmed, K. P. Grehan, et al. , Demonstra- tion of magnetically silent optically pumped magnetome- ters for the TUCAN electric dipole moment experiment, Eur. Phys. J. C 84, 1181 (2024)

2024
[75]

Horrom, R

T. Horrom, R. Singh, J. P. Dowling, et al. , Quantum- enhanced magnetometer with low-frequency squeezing, Phys. Rev. A 86, 023803 (2012)

2012
[76]

Li and I

J. Li and I. Novikova, Improving sensitivity of an amplitude-modulated magneto-optical atomic magne- tometer using squeezed light, J. Opt. Soc. Am. B 39, 2998 (2022)

2022
[77]

Lee and M

S.-K. Lee and M. V. Romalis, Calculation of magnetic ﬁeld noise from high-permeability magnetic shields and conducting objects with simple geometry, J. Appl. Phys. 103, 084904 (2008)

2008

Pith tools

Reviewed August 3, 2026 · model on record in the stance chip above.

[1] [1]

J. C. Allred, R. N. Lyman, T. W. Kornack, et al. , High- sensitivity atomic magnetometer unaﬀected by spin- exchange relaxation, Phys. Rev. Lett. 89, 130801 (2002)

2002

[2] [2]

I. K. Kominis, T. W. Kornack, J. C. Allred, et al. , A subfemtotesla multichannel atomic magnetometer, Na- ture 422, 596 (2003)

2003

[3] [3]

Budker and M

D. Budker and M. V. Romalis, Optical magnetometry, Nat. Phys. 3, 227 (2007)

2007

[4] [4]

W. Xiao, C. Sun, L. Shen, et al. , A movable unshielded magnetocardiography system, Sci. Adv. 9, eadg1746 (2023)

2023

[5] [5]

J. Chen, C. Ye, X. Hou, et al. , Bias calibration of opti- cally pumped magnetometers based on variable sensitiv- ity, Sensors 25, 433 (2025)

2025

[6] [6]

Osborne, J

J. Osborne, J. Orton, O. Alem, et al. , Fully integrated standalone zero ﬁeld optically pumped magnetometer for biomagnetism, SPIE Proc. 10548, 105481G (2018)

2018

[7] [7]

E. Boto, V. Shah, R. M. Hill, et al. , Triaxial detection of the neuromagnetic ﬁeld using optically-pumped mag- netometry: feasibility and application in children, Neu- roImage 252, 119027 (2022)

2022

[8] [8]

O. Alem, K. J. Hughes, I. Buard, et al. , An integrated full-head OPM-MEG system based on 128 zero-ﬁeld sen- sors, Front. Neurosci. 17, 1190310 (2023)

2023