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Related papers: Activation of Non-Local Quantum Resources

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It is well-known that in certain scenarios weakly entangled states can generate stronger nonlocal effects than their maximally entangled counterparts. In this paper, we consider violations of the CHSH Inequality when one party has…

Quantum Physics · Physics 2018-06-13 Daniel Dilley , Eric Chitambar

Entanglement in quantum mechanics contradicts local realism, and is a manifestation of quantum non-locality. Its presence can be detected through the violation of Bell, or CHSH inequalities. Paradigmatic quantum systems provide examples of…

Mesoscale and Nanoscale Physics · Physics 2017-10-25 Alessandro Romito , Yuval Gefen

Quantum nonlocality of several four-qubit states is investigated by constructing a new Bell inequality. These include the Greenberger-Zeilinger-Horne (GHZ) state, W state, cluster state, and the state $|\chi>$ that has been recently…

Quantum Physics · Physics 2013-05-29 Chunfeng Wu , Ye Yeo , L. C. Kwek , C. H. Oh

Nonlocality, evidenced by the violation of Bell inequalities, not only signifies entanglement but also highlights measurement incompatibility in quantum systems. Utilizing the generalized Clauser-Horne-Shimony-Holt (CHSH) Bell inequality,…

Non-classical probability is the underlying feature of quantum mechanics. The emergence of Bell-CHSH non-locality for bipartite systems and linear entanglement inequalities for two-qubit systems has been shown in Adhikary et al. 2020 [Eur.…

Quantum Physics · Physics 2021-10-22 Sooryansh Asthana , Soumik Adhikary , V. Ravishankar

Entanglement and Bell nonlocality are used to describe quantum inseparabilities. Bell-nonlocal states form a strict subset of entangled states. A natural question arises concerning how much territory Bell nonlocality occupies entanglement…

Quantum Physics · Physics 2019-09-04 Xiao-Gang Fan , Zhi-Yong Ding , Fei Ming , Huan Yang , Dong Wang , Liu Ye

Entanglement breaking channels play a significant role in quantum information theory. In this work we investigate qubit channels through their property of `non-locality breaking', defined in a natural way but within the purview of CHSH…

Quantum Physics · Physics 2014-10-30 Rajarshi Pal , Sibasish Ghosh

In the present paper it is demonstrated that Bell's expression for local hidden variable correlation allows one to derive the quantum correlation. This raises questions about the use of Bell inequalities in experiments. In the paper a CHSH…

General Physics · Physics 2010-11-15 J. F Geurdes

We consider quantum systems composed of $N$ qubits, and the family of all Bell's correlation inequalities for two two-valued measurements per site. We show that if a $N$-qubit state $\rho$ violates any of these inequalities, then it is at…

Quantum Physics · Physics 2009-11-07 A. Acin , V. Scarani , M. M. Wolf

Alice and Bob each have half of a pair of entangled qubits. Bob measures his half and then passes his qubit to a second Bob who measures again and so on. The goal is to maximize the number of Bobs that can have an expected violation of the…

Quantum Physics · Physics 2020-09-02 Peter J. Brown , Roger Colbeck

We study the quantum nature of non-Bunch-Davies states in de Sitter space by evaluating CHSH inequality on a localized two-atom system. We show that quantum nonlocality can be generated through the Markovian evolution of two-atom, witnessed…

High Energy Physics - Theory · Physics 2018-10-31 Jun Feng , Xiaoyang Huang , Yao-Zhong Zhang , Heng Fan

We study the nonlocal properties of two-qubit maximally-entangled and N-qubit Greenberger-Horne-Zeilinger states under local decoherence. We show that the (non)resilience of entanglement under local depolarization or dephasing is not…

Quantum Physics · Physics 2015-06-04 Rafael Chaves , Daniel Cavalcanti , Leandro Aolita , Antonio Acín

Entanglement of quantum states is absolutely essential for modern quantum sciences and technologies. It is natural to extend the notion of entanglement to quantum observables dual to quantum states. For quantum states, various separability…

Quantum Physics · Physics 2018-07-18 Ikko Hamamura

We propose a new method for detecting entanglement of two qubits and discuss its relation with the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality. Without the need for full quantum tomography for the density matrix we can experimentally…

Quantum Physics · Physics 2007-05-23 Kai Chen , Ling-An Wu

A systematic approach is presented to construct non-homogeneous two- and three-qubit Bell-type inequalities. When projector-like terms are subtracted from homogeneous two-qubit CHSH polynomial, non-homogeneous inequalities are attained and…

Quantum Physics · Physics 2009-01-22 Mingjun Shi , Changliang Ren , Jiangfeng Du

By establishing CHSH operators and CHSH-type inequalities, we show that any entangled pure state in infinite-dimensional systems is entangled in a $2\otimes2$ subspace. We find that, for infinite-dimensional systems, the corresponding…

Quantum Physics · Physics 2013-08-16 Yu Guo

It is shown that even if the linear entropy of mixed two-qubit state is not smaller then 0.457, Bell - CHSH inequalities can be violated. This contradicts the result obtained in the paper of E. Santos [1].

Quantum Physics · Physics 2007-05-23 Lech Jakobczyk

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

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 consider the Clauser-Horn (CH) inequality for a qubit-qutrit system. We derive the necessary and sufficient conditions for the violation of the inequality as well as some sufficient conditions. Remarkably, we demonstrate the importance…

Quantum Physics · Physics 2026-05-12 Pawel Caban , Pawel Horodecki