Bell scenarios in which nonlocality and entanglement are inversely related

Year: 2014

Authors: Vallone G., Lima G., Gomez E.S., Canas G. Larsson J-A., Mataloni P., Cabello A.

Autors Affiliation: Department of Information Engineering, University of Padova, I-35131 Padova, Italy; Dipartimento di Fisica della “Sapienza” Università di Roma, I-00185 Roma, Italy; Center for Optics and Photonics, MSI-Nucleus on Advanced Optics, Departamento de Fısica, Universidad de Concepcion, 160-C Concepcion, Chile; Institutionen for Systemteknik, Linkopings Universitet, SE-58183 Linkoping, Sweden; Istituto Nazionale di Ottica (INO-CNR), L.go E. Fermi 6, I-50125 Florence, Italy; Departamento de F´ısica Aplicada II, Universidad de Sevilla, E-41012 Sevilla, Spain

Abstract: We show that for two-qubit chained Bell inequalities with an arbitrary number of measurement settings, nonlocality and entanglement are not only different properties but are inversely related. Specifically, we analytically prove that in absence of noise, robustness of nonlocality, defined as the maximum fraction of detection events that can be lost such that the remaining ones still do not admit a local model, and concurrence are inversely related for any chained Bell inequality with an arbitrary number of settings. The closer quantum states are to product states, the harder it is to reproduce quantum correlations with local models. We also show that, in presence of noise, nonlocality and entanglement are simultaneously maximized only when the noise level is equal to the maximum level tolerated by the inequality; in any other case, a more nonlocal state is always obtained by reducing the entanglement. In addition, we observed that robustness of nonlocality and concurrence are also inversely related for the Bell scenarios defined by the tight two-qubit three-setting I-3322 inequality, and the tight two-qutrit inequality I-3.

Journal/Review: PHYSICAL REVIEW A

Volume: 89 (1)      Pages from: 012102  to: 012102

More Information: G.L., E. S. G., and G. C. were supported by the CONICYT, AGCI, FONDECYT 1120067, MilenioP10-030-F, and PIA-CONICYT PFB0824. G. V. was supported by the Strategic-Research-Project QUINTET of the Department of Information Engineering, University of Padova and the Strategic-Research-Project QUANTUMFUTURE of the University of Padova. P. M. acknowledge the Chistera EU project QUASAR. A. C. was supported by Project No. FIS2011-29400 (MINECO, Spain).
DOI: 10.1103/PhysRevA.89.012102

Citations: 12
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-11-17
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here