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Related papers: More non-locality in the three-qubit Greenberger-H…

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It was shown in Phys. Rev. Lett., 87, 230402 (2001) that N (N >= 4) qubits described by a certain one parameter family F of bound entangled states violate Mermin-Klyshko inequality for N >= 8. In this paper we prove that the states from the…

Quantum Physics · Physics 2009-11-07 Dagomir Kaszlikowski , L. C. Kwek , Jingling Chen , C. H. Oh

We show that for all $n\ge3$, an example of an $n$-partite quantum correlation that is not genuinely multipartite nonlocal but rather exhibiting anonymous nonlocality, that is, nonlocal but biseparable with respect to all bipartitions, can…

Quantum Physics · Physics 2014-09-26 Yeong-Cherng Liang , Florian John Curchod , Joseph Bowles , Nicolas Gisin

Analytical and numerical arguments are presented in case of a pair of two-state systems in a singlet state that the threshold visibility for testing Bell's theorem on the entire range of measurement settings is 33.3%. It is also shown that…

Quantum Physics · Physics 2007-05-23 Gyula Bene

The correlations between two qubits belonging to a three-qubit system can violate the Clauser-Horne-Shimony-Holt-Bell inequality beyond Cirel'son's bound [A. Cabello, Phys. Rev. Lett. 88, 060403 (2002)]. We experimentally demonstrate such a…

Quantum Physics · Physics 2007-05-23 Yu-Ao Chen , Tao Yang , An-Ning Zhang , Zhi Zhao , Adan Cabello , Jian-Wei Pan

We investigate two-party quantum teleportation through noisy channels for multi-qubit Greenberger-Horne-Zeilinger (GHZ) states and find which state loses less quantum information in the process. The dynamics of states is described by the…

Quantum Physics · Physics 2014-08-12 Pakhshan Espoukeh , Pouria Pedram

In eliminating the fair sampling assumption, the Greenberger, Horne, Zeilinger (GHZ) theorem is believed to confirm Bell's historic conclusion that local hidden variables are inconsistent with the results of quantum mechanics. The GHZ…

Quantum Physics · Physics 2013-11-28 Louis Sica

We derive a Bell-like inequality involving all correlations in local observables with uncertainty free states and show that the inequality is violated in quantum mechanics for EPR and GHZ states. If the uncertainties are allowed in local…

Quantum Physics · Physics 2007-05-23 Arun Kumar Pati

We relate the nonlocal properties of noisy entangled states to Grothendieck's constant, a mathematical constant appearing in Banach space theory. For two-qubit Werner states $\rho^W_p=p \proj{\psi^-}+(1-p){\one}/{4}$, we show that there is…

Quantum Physics · Physics 2009-11-13 Antonio Acin , Nicolas Gisin , Benjamin Toner

The use of correlated states and measurements promises improvements in the accuracy of frequency metrology and the stability of atomic clocks. However, developing strategies robust against dominant noise processes remains challenging. We…

Quantum Physics · Physics 2024-10-29 Timm Kielinski , Piet O. Schmidt , Klemens Hammerer

Entanglement is an essential resource in many quantum information tasks and entanglement witness is a widely used tool for its detection. In experiments the prepared state generally deviates from the target state due to some noise. Normally…

Quantum Physics · Physics 2020-01-08 You Zhou

The study of quantum nonlocality sharing has garnered significant attention, particularly for two-qubit and three-qubit entangled systems. In this paper, we extend the investigation to $n$-qubit Greenberger-Horne-Zeilinger (GHZ) systems,…

Quantum Physics · Physics 2025-08-12 Sk Sahadat Hossain , Indrani Chattopadhyay

The violation of a Bell inequality implies the existence of nonlocality, making device-independent randomness certification possible. This paper derives a tight upper bound for the maximal quantum violation of Gisin's elegant Bell…

Quantum Physics · Physics 2025-02-14 Dan-Dan Hu , Meng-Yan Li , Fen-Zhuo Guo , Yu-Kun Wang , Hai-Feng Dong , Fei Gao

We consider Bell tests in which the distant observers can perform local filtering before testing a Bell inequality. Notably, in this setup, certain entangled states admitting a local hidden variable model in the standard Bell scenario can…

Quantum Physics · Physics 2016-12-01 Flavien Hirsch , Marco Túlio Quintino , Joseph Bowles , Tamás Vértesi , Nicolas Brunner

This paper is to investigate the effects of quantum noises on entanglement localization by taking an example of reducing a three-qubit Greenberger-Horne-Zeilinger (GHZ) state to a two-qubit entangled state. We consider, respectively, two…

Quantum Physics · Physics 2015-01-19 Xin-Wen Wang , Shi-Qing Tang , Ji-Bing Yuan , Le-Man Kuang

Quantum violation of Bell inequalities is now used in many quantum information applications and it is important to analyze it both quantitatively and conceptually. In the present paper, we analyze violation of multipartite Bell inequalities…

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

The wedge product of vectors has been shown to yield the generalised entanglement measure I-concurrence, wherein the separability of the multiparty qubit system arises from the parallelism of vectors in the underlying Hilbert space of the…

We assess quantum non-locality of multiparty entangled thermal states by studying, quantitatively, both tripartite and quadripartite states belonging to the Greenberger-Horne-Zeilinger (GHZ), W and linear cluster-state classes and showing…

Quantum Physics · Physics 2015-05-18 G. McKeown , F. L. Semiao , H. Jeong , M. Paternostro

Local unitary transforms cannot affect the quantum correlations between two systems sharing an entangled state although they do influence the outcomes of local measurements. By considering local squeezing operations we introduce an extended…

Quantum Physics · Physics 2023-11-15 A. Lezama , A. Auyuanet

We study the problem of closing the detection loophole in three-qubit Bell tests, the experimentally most relevant case beyond the usual bipartite scenario, and show that the minimal detection efficiencies required can be considerably…

Quantum Physics · Physics 2015-08-12 Karoly F. Pal , Tamas Vertesi

We generalize the recently proposed Greenberger-Horne-Zeilinger (GHZ) tripartite protocol [A. Galiautdinov, J. M. Martinis, Phys. Rev. A 78, 010305(R) (2008)] to fully connected networks of weakly coupled qubits interacting by way of…

Quantum Physics · Physics 2015-05-13 Andrei Galiautdinov , Mark W. Coffey , Ron Deiotte