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Related papers: Bipartite nonlocality with a many-body system

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We strengthen the set of Bell-type inequalities presented by Sun & Fei [Phys. Rev. A 74, 032335 (2006)] that give a classification for biseparable correlations and entanglement in tripartite quantum systems. We will furthermore consider the…

Quantum Physics · Physics 2007-07-11 Michael Seevinck

We propose a method for detecting bipartite entanglement in a many-body mixed state based on estimating moments of the partially transposed density matrix. The estimates are obtained by performing local random measurements on the state,…

We estimate the probability of random $N$-qudit pure states violating full-correlation Bell inequalities with two dichotomic observables per site. These inequalities can show violations that grow exponentially with $N$, but we prove this is…

Quantum Physics · Physics 2012-09-11 R. C. Drumond , R. I. Oliveira

We study the separability of symmetric bipartite quantum states and show that a single correlation measurement is sufficient to detect the entanglement of any bipartite symmetric state with a non-positive partial transpose. We also discuss…

Quantum Physics · Physics 2010-02-24 Geza Toth , Otfried Gühne

We derive tight Bell's inequalities for N>2 observers involving more than two alternative measurement settings. We give a necessary and sufficient condition for a general quantum state to violate the new inequalities. The inequalities are…

Quantum Physics · Physics 2009-11-10 Wieslaw Laskowski , Tomasz Paterek , Marek Zukowski , Caslav Brukner

In the case of bipartite two qubits systems, we derive the analytical expression of bound of Bell operator for any given pure state. Our result not only manifest some properties of Bell inequality, for example which may be violated by any…

Quantum Physics · Physics 2011-02-02 Yang Xiang

Based on the optimal quantum violation of suitable Bell's inequality, the device-independent self-testing of state and observables has been reported. It is well-studied that locally commuting or compatible observables cannot be used to…

Quantum Physics · Physics 2023-11-09 Sneha Munshi , A. K. Pan

The maximum observable correlation between the two components of a bipartite quantum system is a property of the joint density operator, and is achieved by making particular measurements on the respective components. For pure states it…

Quantum Physics · Physics 2009-11-13 Michael J. W. Hall , Erika Andersson , Thomas Brougham

We investigate nonlocal quantum correlations arising between multiple two-level impurity atoms coupled to an ultracold bosonic gas. We find that the environment-induced dynamics of the impurity subsystem can generate nonlocal states that…

Quantum Physics · Physics 2023-02-01 Bradley Longstaff , Jonatan Bohr Brask

We introduce a general scheme to detect various multiparticle entanglement structures from global non-permutationally invariant observables. In particular, we derive bounds on the variance of non-permutationally invariant and collective…

Quantum Physics · Physics 2017-08-24 Oliver Marty , Marcus Cramer , Giuseppe Vitagliano , Geza Toth , Martin B. Plenio

The assumption of measurement independence is required for a local deterministic model to conduct a Bell test. The violation of a Bell inequality by such a model implies that this assumption must be relaxed. The degree to which the…

Most of known multipartite Bell inequalities involve correlation functions for all subsystems. They are useless for entangled states without such correlations. We give a method of derivation of families of Bell inequalities for N parties,…

Quantum Physics · Physics 2013-01-08 Marcin Wieśniak , Mohamed Nawareg , Marek Żukowski

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 entangled multipartite systems, specially in pure states, exhibit the phenomenon entanglement monogamy. Such systems also display the phenomenon of Bell nonlocality. Like entanglement monogamy relations, there are Bell monogamy…

Quantum Physics · Physics 2026-01-07 Abhisek Panda , Chandan Datta , Pankaj Agrawal

Entanglement between two separate systems is a necessary resource to violate a Bell inequality in a test of local realism. We demonstrate that to overcome the Bell bound, this correlation must be accompanied by the entanglement between the…

Quantum Physics · Physics 2016-09-07 T. Wasak , A. Smerzi , J. Chwedenczuk

A multipartite quantum state violates a Bell inequality asymptotically if, after jointly processing by general local operations an arbitrarily large number of copies of it, the result violates the inequality. In the bipartite case we show…

Quantum Physics · Physics 2009-11-11 Ll. Masanes

For any finite number of parts, measurements and outcomes in a Bell scenario we estimate the probability of random $N$-qu$d$it pure states to substantially violate any Bell inequality with uniformly bounded coefficients. We prove that under…

Quantum Physics · Physics 2018-02-27 Cristhiano Duarte , Raphael C. Drumond , Roberto I. Oliveira

Quantum nonlocality is usually associated with entangled states by their violations of Bell-type inequalities. However, even unentangled systems, whose parts may have been prepared separately, can show nonlocal properties. In particular, a…

Quantum Physics · Physics 2019-02-06 Saronath Halder , Manik Banik , Sristy Agrawal , Somshubhro Bandyopadhyay

Multipartite entanglement is the premier resource for quantum technologies. Yet, its exact quantification in the laboratory is notoriously challenging, typically requiring the full knowledge of high dimensional quantum states. Here, we…

Quantum Physics · Physics 2026-05-05 Francois Payn , Davide Girolami

We give strong analytic and numerical evidence that, under mild measurement assumptions, two qubits cannot both be recycled to generate Bell nonlocality between multiple independent observers on each side. This is surprising, as under the…

Quantum Physics · Physics 2021-12-21 Shuming Cheng , Lijun Liu , Travis J. Baker , Michael J. W. Hall