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Related papers: More efficient Bell inequalities for Werner states

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In the case of a pair of two-outcome measurements incompatibility is equivalent to Bell nonlocality. Indeed, any pair of incompatible two-outcome measurements can violate the Clauser-Horne-Shimony-Holt Bell inequality, which has been proven…

Quantum Physics · Physics 2018-01-16 Erika Bene , Tamás Vértesi

We show that it is possible to find maximal violations of the CHSH-Bell inequality using only position measurements on a pair of entangled non-relativistic free particles. The device settings required in the CHSH inequality are done by…

Quantum Physics · Physics 2015-05-14 J. Kiukas , R. F. Werner

Bell nonlocality and steering are archetypal characteristics of quantum mechanics that mark a significant departure from conventional classical notions. They basically refer to the presence of quantum correlations between separated systems…

Quantum Physics · Physics 2025-02-07 Dhrumil Patel , Arup Roy , Indranil Chakrabarty , Nirman Ganguly

The problem of closing the detection loophole in Bell tests is investigated in the presence of a limited number of efficient detectors using emblematic multipartite quantum states. To this end, a family of multipartite Bell inequalities is…

Quantum Physics · Physics 2018-08-17 Kamil Kostrzewa , Wieslaw Laskowski , Tamas Vertesi

We present an experimental investigation of two-photon interference using a continuous-wave laser. We demonstrate the violation of the CHSH inequality using the phase randomized weak coherent states from a continuous wave laser. Our…

Quantum Physics · Physics 2023-07-24 Moslem Mahdavifar , S. M. Hashemi Rafsanjani

We propose disturbance-free measurement using a "weak-value" scheme, in which a weakly measured quantum system is post-selected (to the initial state) to confirm that there is no disturbance. The probability of obtaining the non-disturbed…

Quantum Physics · Physics 2018-08-03 Sang Min Lee , Minsu Kim , Heonoh Kim , Han Seb Moon , Sang Wook Kim

The connection between quantum optical nonclassicality and the violation of Bell's inequalities is explored. Bell type inequalities for the electromagnetic field are formulated for general states of quantised radiation and their violation…

Quantum Physics · Physics 2009-10-31 Arvind , N. Mukunda

Nonlinear inequalities based on the quadratic Renyi entropy for mixed two-qubit states are characterized on the Entropy-Concurrence plane. This class of inequalities is stronger than Clauser-Horne-Shimony-Holt (CHSH) inequalities and, in…

Quantum Physics · Physics 2009-11-13 Fabio A. Bovino

Quantum non-locality is an important concept in quantum physics. In this work, we study the quantum non-locality in a fermion many-body system under quasi-periodic disorders. The Clauser-Horne-Shimony-Holt (CHSH) inequality is…

Disordered Systems and Neural Networks · Physics 2024-10-08 Yoshihito Kuno

Entanglement of quasiclassical (coherent) states of two harmonic oscillators leads to striking quantum effects and is useful for quantum technologies. These effects and applications are closely related to nonlocal correlations inherent in…

Quantum Physics · Physics 2019-05-14 Zhi-Rong Zhong , Jian-Qi Sheng , Li-Hua Lin , Shi-Biao Zheng

We consider Bell tests in which the distant observers can perform local filtering before testing a Bell inequality. Notably, in this setup, certain entangled states admitting a local hidden variable model in the standard Bell scenario can…

Quantum Physics · Physics 2016-12-01 Flavien Hirsch , Marco Túlio Quintino , Joseph Bowles , Tamás Vértesi , Nicolas Brunner

We analyze the connection between Bell inequality violations and symmetric extendibility of quantum states. We prove that 2-qubit reduced states of multiqubit symmetric pure states do not violate the Bell Clauser-Horne-Shimony-Holt (CHSH)…

Quantum Physics · Physics 2017-08-09 Meenu Kumari , Shohini Ghose , Robert B. Mann

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

Bell inequalities reveal the fundamentally nonlocal character of quantum mechanics. In this regard, one of the interesting problems is to explore all possible Bell inequalities that demonstrate a gap between local and nonlocal quantum…

Quantum Physics · Physics 2026-02-10 Palash Pandya , Shubhayan Sarkar , Remigiusz Augusiak

The Clauser-Horne-Shimony-Holt (CHSH) inequality is a constraint that local theories must obey. Quantum Mechanics predicts a violation of this inequality in certain experimental settings. Treatments of this subject frequently make…

Quantum Physics · Physics 2015-05-21 Peter Bierhorst

Bell's theorem shows that no hidden-variable model can explain the measurement statistics of a quantum system shared between two parties, thus ruling out a classical (local) understanding of nature. In this work we demonstrate that by…

Quantum Physics · Physics 2022-03-14 Benjamin Morris , Lukas J. Fiderer , Ben Lang , Daniel Goldwater

In this work we show that bipartite quantum states with local Hilbert space dimension n can violate a Bell inequality by a factor of order $\sqrt{n}$ (up to a logarithmic factor) when observables with n possible outcomes are used. A central…

Quantum Physics · Physics 2015-05-14 M. Junge , C. Palazuelos , D. Perez-Garcia , I. Villanueva , M. M. Wolf

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 explore quantum nonlocality in one of the simplest bipartite scenarios. Several new facet-defining Bell inequalities for the {[3 3 3] [3 3 3]} scenario are obtained with their quantum violations analyzed in details. Surprisingly, all…

Quantum Physics · Physics 2018-05-16 Sacha Schwarz , Bänz Bessire , André Stefanov , Yeong-Cherng Liang

Quantum nonlocality is a counterintuitive phenomenon that lies beyond the purview of causal influences. Recently, Bell inequalities have been generalized to the case of quantum inputs, leading to a powerful family of semi-quantum Bell…

Quantum Physics · Physics 2016-08-12 Charles Ci Wen Lim