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Related papers: Bell Inequalities for Graph States

200 papers

Any n-qubit state with n independent perfect correlations is equivalent to a graph state. We present the optimal Bell inequalities for perfect correlations and maximal violation for all classes of graph states with n < 7 qubits. Twelve of…

Quantum Physics · Physics 2009-11-13 Adan Cabello , Otfried Gühne , David Rodriguez

While all bipartite pure entangled states are known to generate correlations violating a Bell inequality, and are therefore nonlocal, the quantitative relation between pure-state entanglement and nonlocality is poorly understood. In fact,…

Quantum Physics · Physics 2018-08-14 Victoria Lipinska , Florian Curchod , Alejandro Máttar , Antonio Acín

First, we present a Bell type inequality for n qubits, assuming that m out of the n qubits are independent. Quantum mechanics violates this inequality by a ratio that increases exponentially with m. Hence an experiment on n qubits violating…

Quantum Physics · Physics 2009-10-31 N. Gisin , H. Bechmann-Pasquinucci

Based on a geometrical argument introduced by Zukowski, a new multisetting Bell inequality is derived, for the scenario in which many parties make measurements on two-level systems. This generalizes and unifies some previous results.…

Quantum Physics · Physics 2009-11-13 Koji Nagata , Wieslaw Laskowski , Tomasz Paterek

Cluster states are a new type of multiqubit entangled states with entanglement properties exceptionally well suited for quantum computation. In the present work, we experimentally demonstrate that correlations in a four-qubit linear cluster…

Quantum Physics · Physics 2009-11-11 Philip Walther , Markus Aspelmeyer , Kevin J. Resch , Anton Zeilinger

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

We show that the rich structure of multipartite entanglement can be tested following a device-independent approach. Specifically we present Bell inequalities for distinguishing between different types of multipartite entanglement, without…

Quantum Physics · Physics 2015-05-30 Nicolas Brunner , James Sharam , Tamas Vertesi

Testing and verifying imperfect multi-qubit quantum devices are important as such noisy quantum devices are widely available today. Bell inequalities are known useful for testing and verifying the quality of the quantum devices from their…

Quantum Physics · Physics 2025-05-16 Bo Yang , Rudy Raymond , Hiroshi Imai , Hyungseok Chang , Hidefumi Hiraishi

We present a family of Bell inequalities for three parties and arbitrarily many outcomes, which can be seen as a natural generalization of the Mermin Bell inequality. For a small number of outcomes, we verify that our inequalities define…

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

A family of Bell-type inequalities is present, which are constructed directly from the "standard" Bell inequalities involving two dichotomic observables per site. It is shown that the inequalities are violated by all the generalized…

Quantum Physics · Physics 2007-05-23 Zeqian Chen

Facet inequalities play an important role in detecting the nonlocality of a quantum state. The number of such inequalities depends on the Bell test scenario. With the increase in the number of parties, measurement outcomes, or/and the…

Quantum Physics · Physics 2023-03-20 Arpan Das , Chandan Datta , Pankaj Agrawal

Bell inequalities for number measurements are derived via the observation that the bits of the number indexing a number state are proper qubits. Violations of these inequalities are obtained from the output state of the nondegenerate…

Quantum Physics · Physics 2022-03-16 Jan-Åke Larsson

We put forward complementary relations of entanglement, coherence, steering inequality violation, and Bell nonlocality for arbitrary three-qubit states. We show that two families of genuinely entangled three-qubit pure states with single…

Quantum Physics · Physics 2023-05-24 Dong-Dong Dong , Xue-Ke Song , Xiao-Gang Fan , Liu Ye , Dong Wang

We find a single parameter family of genuinely entangled three qubit pure states, called the maximally Bell inequality violating states (MBV), which exhibit maximum Bell inequality violation by the reduced bipartite system for a fixed…

Quantum Physics · Physics 2016-11-30 Palash Pandya , Avijit Misra , Indranil Chakrabarty

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

Bell inequalities were meant to test quantum mechanics vs local hidden variable models, but can also be used to verify entanglement. For entanglement verification purposes one assumes the validity of quantum mechanics as well as quantum…

Quantum Physics · Physics 2015-05-13 Pavel Lougovski , S. J. van Enk

Starting from several copies of bipartite noisy entangled states, we design a global and optimal local measurement-based protocol in one- and two-dimensional lattices by which any two or more prefix sites can be connected via entanglement.…

Quantum Physics · Physics 2021-01-04 Ratul Banerjee , Srijon Ghosh , Shiladitya Mal , Aditi Sen De

I derive separability inequalities for Bell correlations of observables in arbitrary pure or mixed $N$ Qudit states in $D^N$-dimensional state space. I find states (a continuum of states if $D>3$) including maximally entangled states which…

Quantum Physics · Physics 2020-02-03 S. M. Roy

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