title: Demonstration of Quantum Nonlocality in the Presence of Measurement Dependence.
abstract: Quantum nonlocality stands as a resource for device independent quantum information processing (DIQIP), such as, for instance, device independent quantum key distribution. We investigate, experimentally, the assumption of limited measurement dependence, i.e., that the measurement settings used in Bell inequality tests or DIQIP are partially influenced by the source of entangled particle and/or by an adversary. Using a recently derived Bell-like inequality [G. Pütz, Phys. Rev. Lett. 113, 190402 (2014)] and a 99% fidelity source of partially entangled polarization photonic qubits, we obtain a clear violation of the inequality, excluding a much larger range of measurement dependent local models than would be possible with an adapted Clauser-Horne-Shimony-Holt (CHSH) inequality. It is therefore shown that the measurement independence assumption can be widely relaxed while still demonstrating quantum nonlocality.
authors.affiliation: Université Nice Sophia Antipolis, Laboratoire de Physique de la Matière Condensée, CNRS UMR 7336, Parc Valrose, 06108 Nice Cedex 2, France.
authors.forename: Djeylan
authors.initials: D
authors.lastname: Aktas
authors.affiliation: Université Nice Sophia Antipolis, Laboratoire de Physique de la Matière Condensée, CNRS UMR 7336, Parc Valrose, 06108 Nice Cedex 2, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Tanzilli
authors.affiliation: Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
authors.forename: Anthony
authors.initials: A
authors.lastname: Martin
authors.affiliation: Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
authors.forename: Gilles
authors.initials: G
authors.lastname: Pütz
authors.affiliation: Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
authors.forename: Rob
authors.initials: R
authors.lastname: Thew
authors.affiliation: Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gisin