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Related papers: Nonlocality and entanglement in the XY model

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Quantum correlation between nodes in a network which consist of several independent sources of entanglement and in multipartite entanglement systems are important for general understanding of the nature of nonlocality, quantum information…

Quantum Physics · Physics 2022-01-25 E. Håkansson , A. Piveteau , S. Muhammad , M. Bourennane

Quantum entanglement plays a crucial role in quantum information processing tasks and quantum mechanics, hence quantifying unknown entanglement is a fundamental task. However, this is also challenging, as entanglement cannot be measured by…

Quantum Physics · Physics 2021-04-27 Xiaodie Lin , Zhenyu Chen , Zhaohui Wei

We compare entanglement with quantum nonlocality employing a geometric structure of the state space of bipartite qudits. Central object is a regular simplex spanned by generalized Bell states. The Collins-Gisin-Linden-Massar-Popescu-Bell…

Quantum Physics · Physics 2015-03-13 Christoph Spengler , Marcus Huber , Beatrix C. Hiesmayr

Ensembles containing orthogonal product states are found to be indistinguishable under local operations and classical communication (LOCC), thereby showing irreversibility in the preparation and distinguishing processes, which is commonly…

Quantum Physics · Physics 2020-09-10 Shiladitya Mal , Aditi Sen De

The results of local measurements on some composite quantum systems cannot be reproduced classically. This impossibility, known as quantum nonlocality, represents a milestone in the foundations of quantum theory. Quantum nonlocality is also…

Quantum Physics · Physics 2015-05-20 D. Cavalcanti , M. L. Almeida , V. Scarani , A. Acin

Entanglement are the non-local correlations permitted by quantum theory, believed to play a fundamental role in a quantum computer. We have investigated these correlations in a number of theoretical models for condensed matter systems. Such…

Quantum Physics · Physics 2007-05-23 Stein Olav Skrøvseth

Entanglement, the Einstein-Podolsky-Rosen (EPR) paradox and Bell's failure of local-hidden-variable (LHV) theories are three historically famous forms of "quantum nonlocality". We give experimental criteria for these three forms of…

Quantum Physics · Physics 2014-05-09 M. D. Reid , Q. Y. He , P. D. Drummond

Non-locality stands nowadays not only as one of the cornerstones of quantum theory, but also plays a crucial role in quantum information processing. Several experimental investigations of nonlocality have been carried out over the years. In…

The unique entanglement measure is concurrence in a 2-qubit pure state. The maximum violation of Bell's inequality is monotonically increasing for this quantity. Therefore, people expect that pure state entanglement is relevant to the…

Quantum Physics · Physics 2022-12-14 Xingyu Guo , Chen-Te Ma

The purposes of the present article are: a) To show that non-locality leads to the transfer of certain amounts of energy and angular momentum at very long distances, in an absolutely strange and unnatural manner, in any model reproducing…

General Physics · Physics 2007-10-05 Athanasios Prikas

The relation between entanglement and nonlocality is discussed in the case of multipartite quantum systems. We show that, for any number of parties, there exist genuinely multipartite entangled states which admit a fully local hidden…

Quantum Physics · Physics 2016-04-06 Joseph Bowles , Jérémie Francfort , Mathieu Fillettaz , Flavien Hirsch , Nicolas Brunner

Bell's 1964 theorem, which states that the predictions of quantum theory cannot be accounted for by any local theory, represents one of the most profound developments in the foundations of physics. In the last two decades, Bell's theorem…

Quantum Physics · Physics 2014-04-22 Nicolas Brunner , Daniel Cavalcanti , Stefano Pironio , Valerio Scarani , Stephanie Wehner

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

Entanglement and violation of Bell inequalities are aspects of quantum nonlocality that have been often confused in the past. It is now known that this equivalence is only true for pure states. Even though almost all the studies of quantum…

Quantum Physics · Physics 2012-06-01 L. Justino , Thiago R. de Oliveira

Quantum entanglement is a key resource in quantum computing and quantum information processing tasks. However, its quantification remains a major challenge since it cannot be directly extracted from physical observables. To address this…

Quantum Physics · Physics 2025-12-29 Shruti Aggarwal , Trasha Gupta , R. K. Agrawal , S. Indu

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

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 report on some quantum properties of physical systems, namely, entanglement, nonlocality, $k$-copy nonlocality (superactivation of nonlocality), hidden nonlocality (activation of nonlocality through local filtering) and the activation of…

Quantum Physics · Physics 2016-09-27 Andrés F. Ducuara , Javier Madroñero , John H. Reina

Quantum mechanics admits correlations that cannot be explained by local realistic models. Those most studied are the standard local hidden variable models, which satisfy the well-known Bell inequalities. To date, most works have focused on…

Quantum Physics · Physics 2017-06-01 Dylan J. Saunders , Adam J. Bennet , Cyril Branciard , Geoff J. Pryde

The universality of quantum theory has been questioned ever since it was proposed. Key to this long-unsolved question is to test whether a given physical system has non-classical features. Here we connect recently proposed witnesses of…