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We present an alternative definition of quantum entanglement for bipartite system based on Bell inequality and operators' noncommutativity. A state is said to be entangled, if the maximum of CHSH expectation value $F_{\max}$ is obtain by…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Xian-Geng Zhao , Shi-Gang Chen

Entanglement, describing the inseparability of a quantum multiparty system, is one of the most intriguing features of quantum mechanics. Violation of Bell inequality, for ruling out the possibility of local hidden variable theories, is…

Quantum Physics · Physics 2017-04-21 Xianxin Guo , Yefeng Mei , Shengwang Du

We present new bell inequalities for arbitrary dimensional bipartite quantum systems. The maximal violation of the inequalities is computed. The Bell inequality is capable of detecting quantum entanglement of both pure and mixed quantum…

Quantum Physics · Physics 2015-05-27 Ming Li , Shao-Ming Fei , Xianqing Li-Jost

The violation of Bell inequalities where both detection and locality loopholes are closed is crucial for device independent assessments of quantum information. While of technological nature, the simultaneous closing of both loopholes still…

Quantum Physics · Physics 2015-06-17 Colin Teo , Jiří Minář , Daniel Cavalcanti , Valerio Scarani

Clauser-Horne-Shimony-Holt inequality for bipartite systems of 4-dimension is studied in detail by employing the unbiased eight-port beam splitters measurements. The uniform formulae for the maximum and minimum values of this inequality for…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Shi-Gang Chen

We describe a simple experimental setting where joint measurements performed on a single (classical or quantum) entity can violate both the Bell-CHSH inequality and the marginal laws (also called no-signaling conditions). Once emitted by a…

Quantum Physics · Physics 2021-09-09 Diederik Aerts , Massimiliano Sassoli de Bianchi

We demonstrate an experimental test of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality which seemingly exhibits correlations beyond the limits imposed by quantum mechanics. Inspired by the idea of Fourier synthesis, we design…

Quantum Physics · Physics 2015-06-17 Jacquiline Romero , Daniel Giovannini , Daniel Tasca , Steve Barnett , Miles Padgett

We prove that there are tripartite quantum states (constructed from random unitaries) that can lead to arbitrarily large violations of Bell inequalities for dichotomic observables. As a consequence these states can withstand an arbitrary…

Quantum Physics · Physics 2008-03-17 D. Perez-Garcia , M. M Wolf , C. Palazuelos , I. Villanueva , M. Junge

We study an asymmetric form of two-mode entangled coherent state (ECS), where the two local amplitudes have different values, for testing the Bell-Clauser-Horne-Shimony-Holt (Bell-CHSH) inequality. We find that the asymmetric ECSs have…

Quantum Physics · Physics 2015-05-20 Chae-Yeun Park , Hyunseok Jeong

Bounds, expressed in terms of d and N, on full Bell locality of a quantum state for $N\geq 3$ nonlocally entangled qudits (of a dimension $d\geq 2$) mixed with white noise are known, to our knowledge, only within full separability of this…

Quantum Physics · Physics 2018-03-28 Elena R. Loubenets

Violation of a Bell inequality guarantees the existence of quantum correlations in a quantum state. A pure bipartite quantum state, having nonvanishing quantum correlation, always violates a Bell inequality. Such correspondence is absent…

Quantum Physics · Physics 2016-07-06 Kunal Sharma , Tamoghna Das , Aditi Sen De , Ujjwal Sen

We evaluate the maximal Clauser-Horne-Shimony-Holt (CHSH) violation for a generic (typically mixed) qubit-qudit state, obtaining easily computable expressions in arbitrary qudit dimension. This represents the optimal (2-2-2) Bell…

Quantum Physics · Physics 2025-10-22 Alexander Bernal , J. Alberto Casas , Jesus M. Moreno

In a general setting, we introduce a new bipartite state property sufficient for the validity of the perfect correlation form of the original Bell inequality for any three bounded quantum observables. A bipartite quantum state with this…

Quantum Physics · Physics 2007-05-23 Elena R. Loubenets

Based on the violation of Bell inequalities, we can verify quantum random numbers by examining the correlation between device inputs and outputs. In this paper, we derive the maximum quantum value of the parity-CHSH inequality for a…

Quantum Physics · Physics 2025-04-21 Guannan Zhang , Jiamin Xu , Ming Li , Shuqian Shen , Lei Li , Shao-ming Fei

To date, most efforts to demonstrate quantum nonlocality have concentrated on systems of two (or very few) particles. It is however difficult in many experiments to address individual particles, making it hard to highlight the presence of…

We derive a new inequality that is necessary and sufficient to show EPR-steering in a scenario employing only correlations between two arbitrary dichotomic measurements on each party. Thus the inequality is a complete steering analogy of…

Quantum Physics · Physics 2017-12-19 Parth Girdhar , Eric G. Cavalcanti

Recently, Fan \textit{et al.} [Mod. Phys. Lett. A 36, 2150223 (2021)], presented a generalized Clauser-Horne-Shimony-Holt (CHSH) inequality, to identify $N$-qubit Greenberger-Horne-Zeilinger (GHZ) states. They showed an interesting…

Quantum Physics · Physics 2022-06-09 Gang-Gang He , Xing-Yan Fan , Fu-Lin Zhang

Euclidean volume ratios between quantum states with positive partial transpose and all quantum states in bipartite systems are investigated. These ratios allow a quantitative exploration of the typicality of entanglement and of its…

Quantum Physics · Physics 2022-07-07 A. Sauer , J. Z. Bernád , H. J. Moreno , G. Alber

We give a set of necessary conditions for locality in bipartite systems, which include and generalize known Bell's inequalities. Each condition corresponds to a specific order of the expansion of random variables defined on graphs, in terms…

Bell-CHSH-like inequalities have been very successful in benchmarking {\it spatial} quantum correlations. However, as this paper illustrates, they are in general not sufficient for benchmarking {\it temporal} quantum correlations. To show…

Quantum Physics · Physics 2026-04-14 Prasenjit Deb , Almut Beige , Lewis A. Clark