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Related papers: Connection among entanglement, mixedness and nonlo…

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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

Entanglement swapping is a process by which two initially independent quantum systems can become entangled and generate nonlocal correlations. To characterize such correlations, we compare them to those predicted by bilocal models, where…

Quantum Physics · Physics 2012-03-23 Cyril Branciard , Denis Rosset , Nicolas Gisin , Stefano Pironio

We propose a scheme to test Bell's inequalities for an arbitrary number of measurement outcomes on entangled continuous variable states. The Bell correlation functions are expressible in terms of phase-space quasiprobability functions with…

Quantum Physics · Physics 2007-05-23 W. Son , C. Brukner , M. S. Kim

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

The question of how Bell nonlocality behaves in bipartite systems of higher dimensions is addressed. By employing the probability of violation of local realism under random measurements as the figure of merit, we investigate the nonlocality…

Bell nonlocality describes a manifestation of quantum mechanics that cannot be explained by any local hidden variable model. Its origin lies in the nature of quantum entanglement, although understanding the precise relationship between…

Quantum Physics · Physics 2022-01-03 Kuntal Sengupta , Rana Zibakhsh , Eric Chitambar , Gilad Gour

We investigate when the quantum correlations of a bipartite system, under the influence of environments with memory, are not reproducible with certainty by a classical local hidden variable model. To this purpose, we compare the dynamics of…

Quantum Physics · Physics 2010-03-30 Bruno Bellomo , Rosario Lo Franco , Giuseppe Compagno

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

Recently Bell-type inequalities were introduced in Phys. Rev. A \textbf{85}, 032119 (2012) to analyze the correlations emerging in an entanglement swapping scenario characterized by independence of the two sources shared between three…

Quantum Physics · Physics 2015-12-31 Kaushiki Mukherjee , Biswajit Paul , Debasis Sarkar

The problem of the relationship between entanglement and two-qubit systems in which it is embedded is central to the quantum information theory. This paper suggests that the concurrence hierarchy as an entanglement measure provides an…

Quantum Physics · Physics 2009-11-11 Mahmoud Abdel-Aty

Quantum systems that have never interacted can become nonlocally correlated through a process called entanglement swapping. To characterize nonlocality in this context, we introduce local models where quantum systems that are initially…

Quantum Physics · Physics 2010-04-27 Cyril Branciard , Nicolas Gisin , Stefano Pironio

We investigate the dynamics of entanglement given by the concurrence of a two-qubit system in the non-Markovian setting. A quantum master equation is derived which is solved in the eigen basis of the system Hamiltonian for X-type initial…

Quantum Physics · Physics 2016-01-21 Muzaffar Qadir Lone

Bell nonlocality refers to correlations between two distant, entangled particles that challenge classical notions of local causality. Beyond its foundational significance, nonlocality is crucial for device-independent technologies like…

Two important ingredients necessary for obtaining Bell nonlocal correlations between two spatially separated parties are an entangled state shared between them and an incompatible set of measurements employed by each of them. We focus on…

Quantum Physics · Physics 2025-05-26 Priya Ghosh , Chirag Srivastava , Swati Choudhary , Ujjwal Sen

Mixed states appear naturally in experiment over pure states. So for studying different notions of nonlocality and their relation with entanglement in realistic scenarios, one needs to consider mixed states. In a recent article [Phys. Rev.…

Quantum Physics · Physics 2016-09-14 Biswajit Paul , Kaushiki Mukherjee , Debasis Sarkar

We present a theoretical study of the relationship between entanglement and entropy in multi-qubit quantum optical systems. Specifically we investigate quantitative relations between the concurrence and linear entropy for a two-qubit mixed…

Quantum Physics · Physics 2009-11-10 Alexandra Olaya-Castro , Neil F. Johnson , Luis Quiroga

We investigate the dynamics of entanglement between two continuous variable quantum systems. The model system consists of two atoms in a harmonic trap which are interacting by a simplified s-wave scattering. We show, that the dynamically…

Quantum Physics · Physics 2009-11-07 Holger Mack , Matthias Freyberger

We propose that the entanglement of mixed states is characterised properly in terms of a probability density function $\mathcal{P}_{\rho}(\mathcal{E})$. There is a need for such a measure since the prevalent measures (such as…

Quantum Physics · Physics 2009-11-13 Shanthanu Bhardwaj , V. Ravishankar

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,…

Consider three qubits A, B, and C which may be entangled with each other. We show that there is a trade-off between A's entanglement with B and its entanglement with C. This relation is expressed in terms of a measure of entanglement called…

Quantum Physics · Physics 2008-12-18 Valerie Coffman , Joydip Kundu , William K. Wootters