Experimental certification of multipartite Bell correlations using only few-body symmetric correlations
Abstract
Certifying Bell correlations in increasingly larger multipartite quantum systems is challenging because conventional Bell inequalities rely on many-body correlations, which become experimentally demanding to estimate as system size grows. Here we demonstrate that multipartite Bell correlations can be certified using few-body permutation-invariant (PI) correlations with a fixed maximal correlation order. We experimentally test few-body PI Bell correlation witnesses tailored for six- and eight-photon postselected Dicke states. The addition of a few four-body correlators is found to significantly enhance the noise tolerance compared with previously studied two-body witnesses: for instance, for six qubits, the selected witness tolerates a white-noise fraction of $p_c\approx0.301$, compared with $p_c\approx0.048$ for the best two-body PI inequality with the same two settings per party. For six and eight photons respectively, we observe violations of the witness bounds by $32$ and $8.9$ standard deviations, arising from postselected polarisation states with fidelities of $0.933(4)$ and $0.916(11)$ to the corresponding half-excitation Dicke states. The witnesses for the six- and eight-photon cases use the same symmetric two- and four-body correlators, just with different coefficients. These results demonstrate an experimentally accessible approach for certifying multipartite Bell correlations in larger systems without requiring full-body correlation measurements.
Authors 12
-
Affiliation as printed
Advanced Institute of Precision Spectroscopy , East China Normal University , Shanghai 200241 , China
-
Centre for Quantum Technologies · National University of Singapore
Affiliation as printed
Centre for Quantum Technologies , National University of Singapore , 3 Science Drive 2 , Singapore 117543 , Singapore
-
Centre for Quantum Technologies · National University of Singapore
Affiliation as printed
Centre for Quantum Technologies , National University of Singapore , 3 Science Drive 2 , Singapore 117543 , Singapore
-
Affiliation as printed
Instituut-Lorentz , Universiteit Leiden , P.O. Box 9506 , 2300 RA Leiden , The Netherlands
⟨aQa L
-
Affiliation as printed
Institute of Quantum Computing and Software , School of Computer Science and Engineering , Sun Yat-sen University , Guangzhou 510006 , China
-
Affiliation as printed
Advanced Institute of Precision Spectroscopy , East China Normal University , Shanghai 200241 , China
-
Affiliation as printed
Advanced Institute of Precision Spectroscopy , East China Normal University , Shanghai 200241 , China
Applied Quantum Algorithms Leiden , The Netherlands
-
Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area
Affiliation as printed
Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong) , Shenzhen 518045 , China
-
Affiliation as printed
Instituut-Lorentz , Universiteit Leiden , P.O. Box 9506 , 2300 RA Leiden , The Netherlands
⟨aQa L
-
Centre for Quantum Technologies · National University of Singapore
Affiliation as printed
Centre for Quantum Technologies , National University of Singapore , 3 Science Drive 2 , Singapore 117543 , Singapore
Department of Physics , National University of Singapore , 2 Science Drive 3 , Singapore 117542 , Singapore
-
Affiliation as printed
Advanced Institute of Precision Spectroscopy , East China Normal University , Shanghai 200241 , China
Shanghai Branch , Hefei National Laboratory , Shanghai 201315 , China
-
Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area
Affiliation as printed
Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong) , Shenzhen 518045 , China
Cited by 0 stored of 0
No patents citing this paper on Lens.org (checked 2026-10-11).