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Related papers: Scalable Bell inequalities for multiqubit systems

200 papers

We introduce inequalities for multi-partite entanglement, derived from the geometry of spin vectors. The criteria are constructed iteratively from cross and dot products between the spins of individual subsystems, each of which may have…

Quantum Physics · Physics 2007-05-23 Gabriel A. Durkin , Christoph Simon

We present a Bell-type inequality for four-qubit systems. Using the inequality we investigate quantum nonlocality of a generic family of states $\left|G_{abcd}\right >$ [Phys. Rev. A 65, 052112 (2002)] and several canonical four-qubit…

Quantum Physics · Physics 2017-06-07 Dong Ding , Fengli Yan , Ting Gao

We analyze conditions for violation of the Bell inequality in the Clauser-Horne-Shimony-Holt form, focusing on the Josephson phase qubits. We start the analysis with maximum violation in the ideal case, and then take into account the…

Superconductivity · Physics 2009-11-13 Abraham G. Kofman , Alexander N. Korotkov

Nonlocality is an essential concept that distinguishes quantum from classical models and has been extensively studied in systems of qubits. For higher-dimensional systems, certain results for their two-level counterpart, like Bell…

Quantum Physics · Physics 2025-08-25 Uta Isabella Meyer , Ivan Šupić , Damian Markham , Frédéric Grosshans

We present a brief historical introduction to the topic of Bell's theorem. Next we present the surprising features of the three particle Greenberger-Horne-Zeilinger (GHZ) states. Finally we shall present a method of analysis of the GHZ…

Quantum Physics · Physics 2007-05-23 D. Kaszlikowski , M. Zukowski

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 this paper we study the nonlocal properties of two-qubit Werner states parameterized by the visibility parameter 0<p<1. New family of Bell inequalities are constructed which prove the two-qubit Werner states to be nonlocal for the…

Quantum Physics · Physics 2009-11-13 T. Vértesi

We propose a generalized Bell inequality for two three-dimensional systems with three settings in each local measurement. It is shown that this inequality is maximally violated if local measurements are configured to be mutually unbiased…

Quantum Physics · Physics 2008-12-01 Se-Wan Ji , Jinhyoung Lee , James Lim , Koji Nagata , Hai-Woong Lee

The proof of Bell's theorem without inequalities by Greenberger, Horne, and Zeilinger (GHZ) is extended to multiparticle multilevel systems. The proposed procedure generalizes previous partial results and provides an operational…

Quantum Physics · Physics 2009-11-06 Adan Cabello

Bell nonlocality provides a device-independent (DI) way to certify quantum randomness, based on which true random numbers can be extracted from the observed correlations without detail characterizations on devices for quantum state…

Quantum Physics · Physics 2026-01-27 Shuai Zhao , Rong Wang , Qi Zhao

Detection and quantification of entanglement in quantum resources are two key steps in the implementation of various quantum-information processing tasks. Here, we show that Bell-type inequalities are not only useful in verifying the…

Quantum Physics · Physics 2011-02-28 Yeong-Cherng Liang , Tamas Vertesi , Nicolas Brunner

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

Bell nonlocality -- the existence of quantum correlations that cannot be explained by classical means -- is certainly one of the most striking features of quantum mechanics. Its range of applications in device-independent protocols is…

Quantum Physics · Physics 2023-12-06 Rafael Santos , Debashis Saha , Flavio Baccari , Remigiusz Augusiak

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

Violation of Mermin's and Svetlichny's inequalities can rule out the predictions of local hidden variable theory and can confirm the existence of true nonlocal correlation for n-particle pure quantum systems. Here we demonstrate the…

Quantum Physics · Physics 2019-05-28 Manoranjan Swain , Amit Rai , Bikash K. Behera , Prasanta K. Panigrahi

We introduce a new method of investigating qutrit nonclassicality by translating qutrit operators to symmetric two-qubit operators. We show that this procedure partially resolves the discrepancy between maximal qutrit entanglement and…

We generalize Bell's inequalities to biparty systems with continuous quantum variables. This is achieved by introducing the Bell operator in perfect analogy to the usual spin-1/2 systems. It is then demonstrated that two-mode squeezed…

Quantum Physics · Physics 2009-11-07 Zeng-Bing Chen , Jian-Wei Pan , Guang Hou , Yong-De Zhang

Techniques developed for device-independent characterizations allow one to certify certain physical properties of quantum systems without assuming any knowledge of their internal workings. Such a certification, however, often relies on the…

Quantum Physics · Physics 2019-07-03 Pei-Sheng Lin , Jui-Chen Hung , Ching-Hsu Chen , Yeong-Cherng Liang

Facet inequalities play an important role in detecting the nonlocality of a quantum state. The number of such inequalities depends on the Bell test scenario. With the increase in the number of parties, measurement outcomes, or/and the…

Quantum Physics · Physics 2023-03-20 Arpan Das , Chandan Datta , Pankaj Agrawal

We explore nonlocality of three-qubit pure symmetric states shared between Alice, Bob and Charlie using the Clauser-Horne-Shimony-Holt (CHSH) inequality. We make use of the elegant parametrization in the canonical form of these states,…

Quantum Physics · Physics 2021-12-28 K. Anjali , Akshata Shenoy Hejamadi , H. S. Karthik , Shradhanjali Sahu , Sudha , A. R. Usha Devi