Genuine Multipartite Entanglement Detection with Imperfect Measurements: Concept and Experiment

Author(s)
Huan Cao, Simon Morelli, Lee A. Rozema, Chao Zhang, Armin Tavakoli, Philip Walther
Abstract

Standard procedures for entanglement detection assume that experimenters can exactly implement specific quantum measurements. Here, we depart from such idealizations and investigate, in both theory and experiment, the detection of genuine multipartite entanglement when measurements are subject to small imperfections. For arbitrary qubits number n, we construct multipartite entanglement witnesses where the detrimental influence of the imperfection is independent of n. In a tabletop four-partite photonic experiment, we demonstrate first how a small amount of alignment error can undermine the conclusions drawn from standard entanglement witnesses and then perform the correction analysis. Furthermore, since we consider quantum devices that are trusted but not perfectly controlled, we showcase advantages in terms of noise resilience as compared to device-independent models.

Organisation(s)
Quantum Optics, Quantum Nanophysics and Quantum Information
External organisation(s)
Basque Center for Applied Mathematics, University of Science and Technology of China (USTC), Lund University, Österreichische Akademie der Wissenschaften (ÖAW)
Journal
Physical Review Letters
Volume
133
No. of pages
7
ISSN
0031-9007
DOI
https://doi.org/10.48550/arXiv.2310.11946
Publication date
10-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics, 103026 Quantum optics
ASJC Scopus subject areas
General Physics and Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/a38c793c-f912-4894-ac55-6c6920c17142