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Related papers: Extended Bell inequality and maximum violation

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Quantum entanglement and quantum nonlocality of $N$-photon entangled states $|\psi_{N m}> =\mathcal{N}_{m}[\cos\gamma|N-m>_{1}|m>_{2} +e^{i\theta_{m}}\sin\gamma|m>_{1}|N-m>_{2}]$ and their superpositions are studied. We indicate that the…

Quantum Physics · Physics 2009-11-11 Yan-Hua Sun , Le-Man Kuang

Homogenization proposed in [Y.-C Wu and M. \.Zukowski, Phys. Rev. A 85, 022119 (2012)] is a procedure to transform a tight Bell inequality with partial correlations into a full-correlation form that is also tight. In this paper, we check…

Quantum Physics · Physics 2015-01-09 Xu Chen , Hong-Yi Su , Zhen-Peng Xu , Yu-Chun Wu , Jing-Ling Chen

We work in the real Hilbert space H_s of hermitian Hilbert-Schmid operators and show that the entanglement witness which shows the maximal violation of a generalized Bell inequality (GBI) is a tangent functional to the convex set S subset…

Quantum Physics · Physics 2009-11-07 R. A. Bertlmann , H. Narnhofer , W. Thirring

We report correlation measurements on two $^9$Be$^+$ ions that violate a chained Bell inequality obeyed by any local-realistic theory. The correlations can be modeled as derived from a mixture of a local-realistic probabilistic distribution…

Quantum Physics · Physics 2017-04-05 T. R. Tan , Y. Wan , S. Erickson , P. Bierhorst , D. Kienzler , S. Glancy , E. Knill , D. Leibfried , D. J. Wineland

D\"{u}r [Phys. Rev. Lett. {\bf 87}, 230402 (2001)] constructed $N$-qubit bound entangled states which violate a Bell inequality for $N\ge 8$, and his result was recently improved by showing that there exists an $N$-qubit bound entangled…

Quantum Physics · Physics 2013-05-29 Dong Pyo Chi , Kabgyun Jeong , Taewan Kim , Kyungjin Lee , Soojoon Lee

Based on the Bell theorem, it has been believed that a theoretical computation of the Bell correlation requires explicit use of an entangled state. Such a physical superposition of light waves occurs in the downconverter sources used in…

Quantum Physics · Physics 2021-01-14 Louis Sica

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…

Quantum Physics · Physics 2014-01-08 G. Vallone , G. Lima , E. S. Gómez , G. Cañas , J. -A. Larsson , P. Mataloni , A. Cabello

A multipartite quantum state violates a Bell inequality asymptotically if, after jointly processing by general local operations an arbitrarily large number of copies of it, the result violates the inequality. In the bipartite case we show…

Quantum Physics · Physics 2009-11-11 Ll. Masanes

The robustness of Bell's inequality (in CHSH form) violation by entangled state in the simultaneous presence of colored and white noise in the system is considered. A twophoton polarization state is modeled by twoparameter density matrix.…

Quantum Physics · Physics 2008-07-02 Ivan S. Dotsenko , Volodymyr G. Voronov

It is shown that Smolin four-qubit bound entangled states [Phys. Rev. A, 63 032306 (2001)] can maximally violate two-setting Bell inequality similar to standard CHSH inequality. Surprisingly this entanglement does not allow for secure key…

Quantum Physics · Physics 2011-12-22 Remigiusz Augusiak , Pawel Horodecki

Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled…

Mesoscale and Nanoscale Physics · Physics 2015-03-31 Simon E. Nigg , Rakesh P. Tiwari , Stefan Walter , Thomas L. Schmidt

We theoretically investigate the joint photodetection probabilities of the biexciton-exciton cascade in single semiconductor quantum dots and analytically derive the density matrix and the Bell's inequalities of the entangled state. Our…

Optics · Physics 2009-11-13 Matthieu Larqué , Isabelle Robert-Philip , Alexios Beveratos

Previous work on Bell's inequality realised in the laboratory has used entangled photons. Here we describe how entangled atoms can violate Bell's inequality, and how these violations can be measured with a very high detection efficiency. We…

Quantum Physics · Physics 2009-11-06 Almut Beige , William J. Munro , Peter L. Knight

Bell correlations are usually formulated for an ideal spin singlet, for which the Bell--CHSH combination reaches the maximal quantum value \(B=-2\sqrt{2}\), independent of detector separation. Here we derive Bell correlations from a more…

Quantum Physics · Physics 2026-05-26 Ju Gao , Fang Shen

Bell's theorem was a cornerstone for our understanding of quantum theory, and the establishment of Bell non-locality played a crucial role in the development of quantum information. Recently, its extension to complex networks has been…

Quantum Physics · Physics 2019-05-23 Francesco Andreoli , Gonzalo Carvacho , Luca Santodonato , Rafael Chaves , Fabio Sciarrino

Nonlocality, evidenced by the violation of Bell inequalities, not only signifies entanglement but also highlights measurement incompatibility in quantum systems. Utilizing the generalized Clauser-Horne-Shimony-Holt (CHSH) Bell inequality,…

A Greenberger Horne Zeilinger (GHZ) entangled state with a phase is crucial for realizing desired multipartite quantum states for practical applications. Here, we report violations of the general Bell inequality (GBI) introduced in [1]…

Quantum Physics · Physics 2023-03-16 Jiho Park , Junghee Ryu , Heonoh Kim , Han Seb Moon

We identify the simplest combinations of entanglement and incompatibility giving the maximum quantum violation for each of the 46 classes of tight Bell inequalities for the (3,2,2) scenario, i.e., three parties, two measurements per party,…

Quantum Physics · Physics 2016-12-30 Sheila López-Rosa , Zhen-Peng Xu , Adán Cabello

I derive separability inequalities for Bell correlations of observables in arbitrary pure or mixed $N$ Qudit states in $D^N$-dimensional state space. I find states (a continuum of states if $D>3$) including maximally entangled states which…

Quantum Physics · Physics 2020-02-03 S. M. Roy

Tests of local realism vs quantum mechanics based on Bell's inequality employ two entangled qubits. We investigate the general case of two entangled quNits, i.e. quantum systems defined in an N-dimensional Hilbert space. Via a numerical…

Quantum Physics · Physics 2009-11-06 D. Kaszlikowski , P. Gnacinski , M. Zukowski , W. Miklaszewski , A. Zeilinger