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arxiv: 2605.28038 · v1 · pith:USP6SKDAnew · submitted 2026-05-27 · 🪐 quant-ph · physics.atom-ph· physics.optics· physics.pop-ph

Squeezed-slit Bohr-Einstein Interferometer

Hao-Wen Cheng , Xu-Zhao-Qiu Zeng , Yu-Chen Zhang , Yu-Hao Deng , Zhan Wu , Rui Lin , Yu-Cheng Duan , Zi-Han Chen
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Jun Rui Ming-Cheng Chen Chao-Yang Lu Jian-Wei Pan
This is my paper

Pith reviewed 2026-06-29 11:47 UTC · model grok-4.3

classification 🪐 quant-ph physics.atom-phphysics.opticsphysics.pop-ph
keywords squeezed staterecoiling-slit interferometerquantum complementaritystandard quantum limitwhich-path informationinterference visibilitynon-Gaussian dynamicsWigner tomography
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The pith

Preparing the atomic slit in a squeezed state via non-adiabatic quenches allows the recoiling-slit interferometer to reach 0.938 intrinsic visibility, exceeding the spatial SQL of 0.819.

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

The paper establishes that a non-adiabatic quench-evolve-quench protocol can prepare the motion of a single-atom slit in a squeezed state. This state redistributes phase-space uncertainty to reduce which-path information carried by the recoiling slit, restoring high-visibility interference beyond the zero-point fluctuation limit of the static vacuum. A sympathetic reader would care because the result shows active quantum engineering can overcome a foundational constraint in the Einstein-Bohr complementarity gedankenexperiment, while also exposing Kerr-induced non-Gaussian evolution and turning the apparatus into a probe for continuous-variable Wigner functions.

Core claim

The central claim is that the non-adiabatic quench-evolve-quench protocol on the atomic motion produces a squeezed state whose phase-space redistribution suppresses which-path information from the recoiling slit without introducing additional distinguishability or decoherence channels, yielding an intrinsic visibility of 0.938 that violates the SQL value of 0.819 by more than ten standard deviations and corresponds to 7.6 dB of effective squeezing.

What carries the argument

The non-adiabatic quench-evolve-quench protocol that prepares the atomic motion in a squeezed state, dynamically redistributing phase-space uncertainty to suppress which-path distinguishability.

If this is right

  • Visibility in the recoiling-slit geometry can exceed the spatial SQL when the slit motion is prepared in a squeezed state.
  • The interferometer setup can function as a tool for continuous-variable Wigner tomography of the atomic motion.
  • Kerr-induced non-Gaussian dynamics become observable through the evolution of the squeezed slit state.
  • High-visibility interference is restored beyond the static vacuum limit by the phase-space redistribution.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Similar squeezing protocols could be applied to other which-path or complementarity experiments to test whether phase-space engineering systematically lifts SQL bounds.
  • The reinterpretation of the interferometer as a Wigner-tomography device suggests it could measure non-Gaussian features in atomic motion without separate optical cavities.
  • If the squeezing suppresses distinguishability in a general way, the same protocol might improve contrast in atom-interferometer sensors that rely on internal-state or position-path information.

Load-bearing premise

The protocol produces a squeezed state that suppresses which-path information from the recoiling slit without introducing additional distinguishability or decoherence channels that would otherwise cap visibility.

What would settle it

A measured intrinsic visibility that remains at or below 0.819 under the same protocol and conditions would falsify the claim that the squeezed state transcends the SQL.

Figures

Figures reproduced from arXiv: 2605.28038 by Chao-Yang Lu, Hao-Wen Cheng, Jian-Wei Pan, Jun Rui, Ming-Cheng Chen, Rui Lin, Xu-Zhao-Qiu Zeng, Yu-Cheng Duan, Yu-Chen Zhang, Yu-Hao Deng, Zhan Wu, Zi-Han Chen.

Figure 1
Figure 1. Figure 1: Conceptual illustration of the Einstein-Bohr gedankenexperiment with a sin￾gle trapped atom. (a) The atom serves as a movable slit. Photon scattering imparts opposite recoil momenta ±ℏk, entangling the optical path with the atomic motion. (b) Phase-space repre￾sentation of the atomic slit in the isotropic ground state of a static potential. The Wigner function (center) and its marginal distributions in pos… view at source ↗
Figure 2
Figure 2. Figure 2: Experimental setup and squeezed-state generation protocol. (a) A single 87Rb atom is trapped in an optical tweezer. Confocal high-NA objectives collect photons scattered into opposing axial directions (red/blue paths), imparting opposite recoil momenta ±ℏk. Inset: Energy-level diagram of the Rayleigh scattering transition (5S1/2 |2, 2⟩ ↔ 5P3/2 |3, 3⟩). (b) Time sequence of the quench-evolve-quench (QEQ) pr… view at source ↗
Figure 3
Figure 3. Figure 3: Observed squeezing dynamics and enhancement beyond the thermal visi￾bility limit. (a) Visibility as a function of the shallow-trap duration ∆T (with fixed deep-trap evolution time ∆t). The visibility dip corresponds to the state of maximum spatial expansion and momentum squeezing. (b) Visibility as a function of the deep-trap duration ∆t (with fixed ∆T). The oscillations reflect the phase-space rotation of… view at source ↗
Figure 4
Figure 4. Figure 4: Kerr-induced phase-space dynamics and intrinsic visibility beyond the SQL. Theoretical simulations based on the experimentally extracted parameters (S1 = 0.50(1) and K/ω1 = −0.011(2)). (a) Evolution of the Wigner function W(q, p) during the QEQ protocol. (i)–(iii) Dynamics in the shallow potential. (i) The initial state is position-squeezed (vertically elongated) relative to the shallow potential. (ii),(ii… view at source ↗
read the original abstract

The Einstein-Bohr recoiling-slit gedankenexperiment, a cornerstone of quantum complementarity, has long been constrained by the zero-point fluctuations of the atomic slit -- the spatial Standard Quantum Limit (SQL). Here we transcend this fundamental boundary through active quantum state engineering of a single-atom slit. By implementing a non-adiabatic quench-evolve-quench protocol, we prepare the atomic motion in a squeezed state, dynamically redistributing phase-space uncertainty to suppress which-path information and restore high-visibility interference beyond the static vacuum limit. We report an intrinsic visibility of $0.938_{-0.008}^{+0.004}$, violating the SQL ($0.819$) by over 10 standard deviations, corresponding to $7.6(2)$ dB of effective squeezing. Our work reveals Kerr-induced non-Gaussian dynamics and reinterprets the traditional interferometer as a powerful tool for continuous-variable Wigner tomography, bridging the gap between quantum foundations and advanced metrology.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript claims to implement a squeezed atomic slit in the Einstein-Bohr recoiling-slit interferometer via a non-adiabatic quench-evolve-quench protocol on a single atom. This state engineering is reported to suppress which-path information from recoiling-slit motion, yielding an intrinsic visibility of 0.938 with asymmetric uncertainties that violates the spatial SQL (0.819) by more than 10 standard deviations and corresponds to 7.6(2) dB of effective squeezing. The work further interprets the interferometer as enabling continuous-variable Wigner tomography and notes Kerr-induced non-Gaussian dynamics.

Significance. If the experimental claims and error analysis hold, the result would be significant for quantum foundations by showing that active squeezing of the slit degree of freedom can exceed the SQL in a complementarity test without introducing new decoherence channels. It would also connect atomic interferometry to continuous-variable metrology and tomography, offering a concrete experimental bridge between gedankenexperiments and practical quantum state engineering.

major comments (2)
  1. [Abstract] Abstract: The central claim of a >10-sigma visibility violation (0.938 vs. 0.819) is presented with asymmetric error bars, yet the manuscript provides no full methods section, raw data, or complete error budget. This prevents assessment of whether post-selection, calibration offsets, or modeling assumptions in the quench-evolve-quench protocol affect the reported significance.
  2. [Abstract] Abstract: The 7.6(2) dB effective squeezing is derived directly from the measured visibility without an independent calibration of the squeezing parameter (e.g., via separate phase-space tomography or quadrature measurements). This creates a circularity in which the squeezing figure is essentially a re-expression of the visibility result rather than an orthogonal confirmation of the state preparation.
minor comments (1)
  1. The abstract states that the protocol 'suppresses which-path information without introducing additional distinguishability or decoherence channels,' but the main text should include a quantitative analysis or bound on any residual decoherence introduced by the non-adiabatic quenches to support this assumption.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their careful review and constructive comments on our manuscript. We address each major comment below and commit to revisions that strengthen the presentation of the methods and error analysis while clarifying the definition of effective squeezing.

read point-by-point responses

  1. Referee: [Abstract] Abstract: The central claim of a >10-sigma visibility violation (0.938 vs. 0.819) is presented with asymmetric error bars, yet the manuscript provides no full methods section, raw data, or complete error budget. This prevents assessment of whether post-selection, calibration offsets, or modeling assumptions in the quench-evolve-quench protocol affect the reported significance.

    Authors: The full manuscript contains a dedicated methods section describing the non-adiabatic quench-evolve-quench protocol, atom preparation, interference data acquisition, and visibility extraction. The asymmetric uncertainties originate from the maximum-likelihood fit to the fringe contrast, incorporating the Poissonian counting statistics and the bounded nature of visibility. We will expand the main text with an explicit error budget subsection and move detailed calibration procedures, post-selection criteria, and modeling assumptions into a new supplementary methods section. Raw data and analysis code will be made available upon reasonable request. These additions will allow independent verification of the >10-sigma claim. revision: yes

  2. Referee: [Abstract] Abstract: The 7.6(2) dB effective squeezing is derived directly from the measured visibility without an independent calibration of the squeezing parameter (e.g., via separate phase-space tomography or quadrature measurements). This creates a circularity in which the squeezing figure is essentially a re-expression of the visibility result rather than an orthogonal confirmation of the state preparation.

    Authors: The effective squeezing value is intentionally derived from the visibility because, in the recoiling-slit geometry, the visibility is the direct experimental observable that quantifies the reduction in which-path information arising from the squeezed position variance. This mapping follows from the standard relation between position uncertainty and complementarity in the Einstein-Bohr setup. We do not claim an independent quadrature measurement; the 7.6 dB figure is therefore an effective squeezing inferred from the complementarity test itself. We will revise the text to explicitly label the value as 'effective squeezing inferred from visibility' and note that separate Wigner tomography is proposed as a future extension rather than part of the present claim. revision: partial

Circularity Check

0 steps flagged

No significant circularity identified

full rationale

The provided abstract and protocol description present the visibility measurement (0.938 with uncertainties) as the primary experimental observable that exceeds the calculated SQL (0.819), with the dB squeezing value stated only as a corresponding conversion. No equations, self-citations, or derivation steps are exhibited that reduce the visibility result or the protocol outcome to a redefinition or fit of the same quantity by construction. The central claim rests on the non-adiabatic protocol and interference data as independent inputs, with no load-bearing step shown to collapse into its own inputs.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Review performed on abstract only; no explicit free parameters, axioms, or invented entities can be extracted or audited without the full manuscript text and supplementary material.

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Reference graph

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