Optimized squeezing for accurate differential sensing under large phase noise
Year: 2025
Authors: Corgier R., Malitesta M., Sidorenkov L.A., Dos Santos F.P., Rosi G., Tino G.M., Smerzi A., Salvi L., Pezzč L.
Autors Affiliation: Univ Lille, Univ PSL, Sorbonne Univ, LTE,Observ Paris,LNE,CNRS, 61 Ave Observ, F-75014 Paris, France; Consiglio Nazl Ric INO CNR, Ist Nazl Ott, Largo Enrico Fermi 6, I-50125 Florence, Italy; Univ Firenze, Dept Phys & Astron, Via Sansone 1, I-50019 Sesto Fiorentino, Italy; Ist Nazl Fis Nucl INFN, Via Sansone 1, I-50019 Sesto Fiorentino, Italy; European Lab Nonlinear Spect LENS, Via Nello Carrara 1, I-50019 Sesto Fiorentino, Italy; QSTAR, Largo Enrico Fermi 2, I-50125 Florence, Italy.
Abstract: Atom interferometers are reaching sensitivities fundamentally constrained by quantum fluctuations. A main challenge is to integrate entanglement into quantum sensing protocols to enhance precision while ensuring robustness against noise and systematics. Here, we theoretically investigate differential phase measurements with two atom interferometers using spin-squeezed states of N atoms, accounting for common-mode phase noise spanning the full 2 pi range. We estimate the differential signal using model-free ellipse fitting, a robust method requiring no device calibration and resilient to additional noise sources. Our results show that spin-squeezing enables sensitivities below the standard quantum limit (SQL). Specifically, we identify optimal squeezed states that minimize the differential phase uncertainty, scaling as N-2/3, thus overcoming the SQL by a factor N1/6, while eliminating the bias inherent in ellipse fitting methods. We benchmark our protocol against the Cram & eacute;r-Rao bound and compare it with hybrid methods that incorporate auxiliary classical sensors. Our findings provide a pathway to robust and high-precision atom interferometry, in realistic noisy environments and using readily available states and estimation methods.
Journal/Review: QUANTUM SCIENCE AND TECHNOLOGY
Volume: 10 (4) Pages from: 45016-1 to: 45016-17
More Information: This research has been carried out in the frame of the QuantERA project SQUEIS (Squeezing enhanced inertial sensing), funded by the European Union’s Horizon Europe Programme, the Agence Nationale de la Recherche (ANR-22-QUA2-0006). We also acknowledge financial support from the European Union’s Horizon 2020 research and innovation programme-Qombs Project, FET Flagship on Quantum Technologies Grant No. 820419. RC, LAS and FP acknowledge the support from a government grant managed by the Agence Nationale de la Recherche under the Plan France 2030 with the reference ’ANR-22-PETQ-0005’. LS and GR acknowledge financial support from the PRIN 2022 Project ’Quantum Sensing and Precision Measurements with Nonclassical States’. MM and GMT acknowledge acknowledge funding from the European Union’s Next Generation EU Programme IR0000016 I-PHOQS Integrated Infrastructure Initiative in Photonic and Quantum Sciences. LS and GMT acknowledge financial support from PNRR MUR Project No. PE0000023-NQSTI.KeyWords: spin-squeezing; quantum sensing; differential measurements; ellipse fitting; quantum metrologyDOI: 10.1088/2058-9565/adf2d8
