Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping

Robin Corgier; Marco Malitesta; Augusto Smerzi; Luca Pezzè

doi:10.22331/q-2023-03-30-965

Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping

Robin Corgier^1,2, Marco Malitesta¹, Augusto Smerzi¹, and Luca Pezzè¹

¹QSTAR, INO-CNR and LENS, Largo Enrico Fermi 2, 50125 Firenze, Italy.
²LNE-SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université 61 avenue de l’Observatoire, 75014 Paris, France

Published:	2023-03-30, volume 7, page 965
Eprint:	arXiv:2205.09698v3
Doi:	https://doi.org/10.22331/q-2023-03-30-965
Citation:	Quantum 7, 965 (2023).

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Abstract

Thanks to common-mode noise rejection, differential configurations are crucial for realistic applications of phase and frequency estimation with atom interferometers. Currently, differential protocols with uncorrelated particles and mode-separable settings reach a sensitivity bounded by the standard quantum limit (SQL). Here we show that differential interferometry can be understood as a distributed multiparameter estimation problem and can benefit from both mode and particle entanglement. Our protocol uses a single spin-squeezed state that is mode-swapped among common interferometric modes. The mode swapping is optimized to estimate the differential phase shift with sub-SQL sensitivity. Numerical calculations are supported by analytical approximations that guide the optimization of the protocol. The scheme is also tested with simulation of noise in atomic clocks and interferometers.

Popular summary

Thanks to common-mode noise rejection, differential configurations are crucial for realistic applications of phase and frequency estimation with atom interferometers.
Currently, differential protocols with uncorrelated particles and mode-separable settings reach a sensitivity bounded by the standard quantum limit (SQL).
Here we show that differential interferometry can be understood as a distributed multiparameter estimation problem and can benefit from both mode and particle entanglement.
Our protocol uses a single spin-squeezed state that is mode-swapped among common interferometric modes.
The mode swapping is optimized to estimate the differential phase shift with sub-SQL sensitivity.

► BibTeX data

@article{Corgier2023quantumenhanced,
  doi = {10.22331/q-2023-03-30-965},
  url = {https://doi.org/10.22331/q-2023-03-30-965},
  title = {Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping},
  author = {Corgier, Robin and Malitesta, Marco and Smerzi, Augusto and Pezz{\`{e}}, Luca},
  journal = {{Quantum}},
  issn = {2521-327X},
  publisher = {{Verein zur F{\"{o}}rderung des Open Access Publizierens in den Quantenwissenschaften}},
  volume = {7},
  pages = {965},
  month = mar,
  year = {2023}
}

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