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Related papers: Quantum nonlocality of four-qubit entangled states

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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 show that the continuous-variable analogues to the multipartite entangled Greenberger-Horne-Zeilinger states of qubits violate Bell-type inequalities imposed by local realistic theories. Our results suggest that the degree of nonlocality…

Quantum Physics · Physics 2009-11-06 P. van Loock , Samuel L. Braunstein

It remains an open question whether every pure multipartite state that is genuinely entangled is also genuinely nonlocal. Recently, a new general construction of Bell inequalities allowing the detection of genuine multipartite nonlocality…

Quantum Physics · Physics 2024-09-23 Ignacy Stachura , Owidiusz Makuta , Remigiusz Augusiak

A well-known manifestation of quantum entanglement is that it may lead to correlations that are inexplicable within the framework of a locally causal theory --- a fact that is demonstrated by the quantum violation of Bell inequalities. The…

Quantum Physics · Physics 2012-12-07 Yeong-Cherng Liang , Lluis Masanes , Denis Rosset

We provide a method to describe quantum nonlocality for $n$-qubit systems. By treating the correlation function as an $n$-index tensor, we derive a generalized Bell inequality. Taking generalized Greenberger-Horne-Zeilinger (GHZ) state for…

Quantum Physics · Physics 2021-05-11 Dong Ding , Yingqiu He , Fengli Yan , Ting Gao

We prove that for a three-qubit system in the Greenberger-Horne-Zeilinger (GHZ) state, locality per se is in conflict with the perfect GHZ correlations. The proof does not in any way use the realism assumption and can lead to a refutation…

Quantum Physics · Physics 2007-05-23 Zeng-Bing Chen , Nai-Le Liu , Sixia Yu , Yong-De Zhang

Multipartite quantum states may exhibit different types of quantum entanglement in that they cannot be converted into each other by local quantum operations only, and fully understanding mathematical structures of different types of…

Quantum Physics · Physics 2020-06-24 Lijinzhi Lin , Zhaohui Wei

We analyze the relationship between tripartite entanglement and genuine tripartite nonlocality for 3-qubit pure states in the GHZ class. We consider a family of states known as the generalized GHZ states and derive an analytical expression…

Quantum Physics · Physics 2009-07-02 S. Ghose , N. Sinclair , S. Debnath , P. Rungta , R. Stock

Systems of four nonbinary particles, each having three or more internal states, exhibit maximally entangled states that are inaccessible to four qubits. This breaks the pattern of two- and three-particle systems, in which the existing graph…

Quantum Physics · Physics 2015-06-23 Mario Gaeta , Andrei Klimov , Jay Lawrence

The correlations in quantum networks have attracted strong interest with new types of violations of the locality. The standard Bell inequalities cannot characterize the multipartite correlations that are generated by multiple sources. The…

Quantum Physics · Physics 2018-11-19 Ming-Xing Luo

We study the nonlocality of arbitrary dimensional bipartite quantum states. By computing the maximal violation of a set of multi-setting Bell inequalities, an analytical and computable lower bound has been derived for general two-qubit…

Quantum Physics · Physics 2015-09-04 Ming Li , Tinggui Zhang , Bobo Hua , Shao-Ming Fei , Xianqing Li-Jost

We propose an alternative evaluation of quantum entanglement by measuring the maximum violation of the Bell's inequality without performing a partial trace operation. This proposal is demonstrated by bridging the maximum violation of the…

Quantum Physics · Physics 2017-10-11 Po-Yao Chang , Su-Kuan Chu , Chen-Te Ma

A set of Bell inequalities classifying the quantum entanglement of four-qubit states is presented. These inequalities involve only two measurement settings per observer and can characterize fully separable, bi-separable and tri-separable…

Quantum Physics · Physics 2013-07-26 Hui Zhao , Xing-Hua Zhang , Shao-Ming Fei , Zhi-Xi Wang

The hierarchy of nonlocality and entanglement in multipartite systems is one of the fundamental problems in quantum physics. We study this topic in three-qubit systems considering the entanglement classification of stochastic local…

Quantum Physics · Physics 2022-06-07 Dian Zhu , Gang-Gang He , Fu-Lin Zhang

For a multipartite quantum state, the maximal violation of all Bell inequalities constitutes a measure of its nonlocality [Loubenets, J. Math. Phys. 53, 022201 (2012)]. In the present article, for the maximal violation of Bell inequalities…

Quantum Physics · Physics 2022-07-06 Elena R. Loubenets , Min Namkung

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

The aim of this thesis is to investigate quantum entanglement and quantum nonlocality of bipartite finite-dimensional systems (bipartite qudits). Entanglement is one of the most fascinating non-classical features of quantum theory, and…

Quantum Physics · Physics 2009-07-09 Christoph Spengler

We investigate the nonlocality of Schmidt-correlated (SC) states, and present analytical expressions of the maximum violation value of Bell inequalities. It is shown that the violation of Clauser-Horne-Shimony-Holt (CHSH) inequality is…

Quantum Physics · Physics 2015-05-28 Ming-Jing Zhao , Zong-Guo Li , Bo Li , Shao-Ming Fei , Zhi-Xi Wang , Xian-Qing Li-Jost

Maximally entangled states should maximally violate the Bell inequality. In this paper, it is proved that all two-qubit states that maximally violate the Bell-Clauser-Horne-Shimony-Holt inequality are exactly Bell states and the states…

Quantum Physics · Physics 2009-11-10 Zeqian Chen

The nature of quantum correlations in networks featuring independent sources of entanglement remains poorly understood. Here, focusing on the simplest network of entanglement swapping, we start a systematic characterization of the set of…

Quantum Physics · Physics 2021-04-21 Nicolas Gisin , Quanxin Mei , Armin Tavakoli , Marc-Olivier Renou , Nicolas Brunner