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Related papers: Quantum nonlocality of four-qubit entangled states

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For the maximal violation of all Bell inequalities by an arbitrary pure two-qudit state of any dimension, we derive a new lower bound expressed via the concurrence of this pure state. This new lower bound and the upper bound on the maximal…

Quantum Physics · Physics 2023-08-17 Elena R. Loubenets , Sergey Kuznetsov , Louis Hanotel

The Clauser-Horne-Shimony-Holt inequality was originally proposed as a Bell inequality to detect nonlocality in bipartite systems. However, it can also be used to certify the nonlocality of multipartite quantum states. We apply this to…

Quantum Physics · Physics 2014-06-02 Rafael Chaves , Antonio Acín , Leandro Aolita , Daniel Cavalcanti

We discuss a family of W-class states describing three-qubit systems. For such systems, we analyze the relations between the entanglement measures and the nonlocality parameter for a two-mode mixed state related to the two-qubit subsystem.…

Quantum Physics · Physics 2025-01-08 Joanna K. Kalaga , Wiesław Leoński , Jan Peřina

We derive a multipartite generalized Bell inequality which involves the entire range of settings for each of the local observers. Especially, it is applied to show non-local behavior of a six-qubit mixture of Greenberger-Horne-Zeilinger…

Quantum Physics · Physics 2009-11-13 Koji Nagata

Whether every pure genuinely multipartite entangled (GME) state necessarily exhibits genuine multipartite nonlocality (GMNL) remains an open question. By combining a recently proposed Bell inequality [I. Stachura \textit{et al.},…

Quantum Physics · Physics 2025-10-16 Jakub Wójcik , Wojciech Bruzda , Ignacy Stachura , Remigiusz Augusiak

We analyze sharing Bell-type nonlocal correlation between two distant parties with optical hybrid states comprising a single photon polarization state and a multiphoton coherent state. By deploying entanglement swapping over the coherent…

Quantum Physics · Physics 2025-10-01 Subhankar Bera , Soumyakanti Bose , Hyunseok Jeong , Archan S Majumdar

Greenberger-Horne-Zeilinger states are intuitively known to be the most non-classical ones. They lead to the most radically nonclassical behavior of three or more entangled quantum subsystems. However, in case of two-dimensional systems, it…

Quantum Physics · Physics 2016-10-07 Marcin Wieśniak , Arijit Dutta , Junghee Ryu

We introduce a geometric framework for studying Bell nonlocality in Hilbert space, where, for a given quantum state, nonlocality is quantified by the distance between the state and the set of local states. This approach applies to any Bell…

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

Nonlocality and entanglement are not only the fundamental characteristics of quantum mechanics but also important resources for quantum information and computation applications. Exploiting the quantitative relationship between the two…

Quantum Physics · Physics 2020-04-20 Zhaofeng Su , Haisheng Tan , Xiangyang Li

It is shown that the correlations between two qubits selected from a trio prepared in a W state violate the Clauser-Horne-Shimony-Holt inequality more than the correlations between two qubits in any quantum state. Such a violation beyond…

Quantum Physics · Physics 2009-07-28 Adan Cabello

Bipartite and multipartite entangled states are basic ingredients for constructing quantum networks and their accurate verification is crucial to the functioning of the networks, especially for untrusted networks. Here we propose a simple…

Quantum Physics · Physics 2021-12-28 Yun-Guang Han , Zihao Li , Yukun Wang , Huangjun Zhu

In multipartite Bell scenarios, we study the nonlocality robustness of the Greenberger-Horne-Zeilinger (GHZ) state. When each party performs planar measurements forming a regular polygon, we exploit the symmetry of the resulting correlation…

Quantum Physics · Physics 2024-02-09 Sébastien Designolle , Tamás Vértesi , Sebastian Pokutta

In this paper, we investigate the genuine three-way nonlocality which is recognized as the strongest form of tripartite correlations. We consider theoretically and experimentally a series of suitable Bell-type inequalities a violation of…

Quantum Physics · Physics 2019-05-22 Artur Barasiński , Antonín Černoch , Karel Lemr , Jan Soubusta

There exist bipartite entangled states whose violations of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality can be observed by a single Alice and arbitrarily many sequential Bobs [Phys. Rev. Lett. 125, 090401 (2020)]. Here we consider its…

Quantum Physics · Physics 2023-11-08 Ya Xi Mao-Sheng Li Libin Fu , Zhu-Jun Zheng

Quantum nonlocality is tested for an entangled coherent state, interacting with a dissipative environment. A pure entangled coherent state violates Bell's inequality regardless of its coherent amplitude. The higher the initial nonlocality,…

Quantum Physics · Physics 2009-11-07 D. Wilson , H. Jeong , M. S. Kim

The first characterization of mixed-state entanglement was achieved for two-qubit states in Werner's seminal work [Phys. Rev. A 40, 4277 (1989)]. A physically important extension of this result concerns mixtures of a pure entangled state…

Quantum Physics · Physics 2015-06-15 Christopher Eltschka , Jens Siewert

The hybrid entangled states generated, e.g., in a trapped-ion or atom-cavity system, have exactly one ebit of entanglement, but are not maximally entangled. We demonstrate this by showing that they violate, but in general do not maximally…

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

For a class of mixed two -qubit states we show that it is not possible to discriminate between states violating or non - violating Bell - CHSH inequalities, knowing only their entanglement and mixedness. For a large set of possible values…

Quantum Physics · Physics 2009-11-10 L. Derkacz , L. Jakobczyk

We generalize the Greenberger-Horne-Zeilinger nonlocality without inequalities argument to cover the case of arbitrary mixed statistical operators associated to three-qubits quantum systems. More precisely, we determine the radius of a ball…

Quantum Physics · Physics 2009-11-13 GianCarlo Ghirardi , Luca Marinatto