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Related papers: Multi-Partite Entanglement Inequalities via Spin V…

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In quantum physics, multiparticle systems are described by quantum states acting on tensor products of Hilbert spaces. This product structure leads to the distinction between product states and entangled states; moreover, one can quantify…

Quantum Physics · Physics 2026-03-06 Lisa T. Weinbrenner , Albert Rico , Kenneth Goodenough , Xiao-Dong Yu , Otfried Gühne

A necessary and sufficient entanglement criterion based on variances of Mermin-Klyshko's Bell operators is proved for multiqubit pure states. Contrary to Bell's inequalities, entangled pure states strictly satisfy a quadratic inequality but…

Quantum Physics · Physics 2015-06-26 Zeqian Chen , Quanhua Xu

We present a new set of inseparabilty inequalities to detect entanglement in $N$-spin states. These are based on negative partial transposition and involve collective spin-spin correlations of any two partitions of the entire system. They…

Quantum Physics · Physics 2016-08-08 Asoka Biswas

The nonlocal correlations of multipartite entangled states can be reproduced by a classical model if sufficiently many parties join together or if sufficiently many parties broadcast their measurement inputs. The maximal number m of groups…

Quantum Physics · Physics 2009-08-27 Jean-Daniel Bancal , Cyril Branciard , Nicolas Gisin , Stefano Pironio

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…

We provide an analytical tripartite-study from the generalized $R$-matrix. It provides the upper bound of the maximum violation of Mermin's inequality. For a generic 2-qubit pure state, the concurrence or $R$-matrix characterizes the…

Quantum Physics · Physics 2023-01-11 Xingyu Guo , Chen-Te Ma

We derive a family of necessary separability criteria for finite-dimensional systems based on inequalities for variances of observables. We show that every pure bipartite entangled state violates some of these inequalities. Furthermore, a…

Quantum Physics · Physics 2016-09-08 Otfried Guehne

In this paper we obtain violations of general bipartite Bell inequalities of order $\frac{\sqrt{n}}{\log n}$ with $n$ inputs, $n$ outputs and $n$-dimensional Hilbert spaces. Moreover, we construct explicitly, up to a random choice of signs,…

Quantum Physics · Physics 2011-08-30 Marius Junge , Carlos Palazuelos

We perform a detailed analysis of the possible violation of various Bell-type inequalities for systems of vector boson-antiboson pairs. Considering the general case of an overall scalar state of the bipartite system, we identify two…

Quantum Physics · Physics 2023-08-02 Alan J. Barr , Pawel Caban , Jakub Rembieliński

The study on the entanglement polygon inequality of multipartite systems has attracted much attention. However, most of the results are on pure states. Here we consider the property for a class of mixed states, which are the reduced density…

Quantum Physics · Physics 2024-07-08 Xian Shi

We consider a bipartite scenario where two parties hold ensembles of $1/2$-spins which can only be measured collectively. We give numerical arguments supporting the conjecture that in this scenario no Bell inequality can be violated for…

Quantum Physics · Physics 2019-10-30 Enky Oudot , Jean-Daniel Bancal , Pavel Sekatski , Nicolas Sangouard

The structure of Bell-type inequalities detecting genuine multipartite non-locality, and hence detecting genuine multipartite entanglement, is investigated. We first present a simple and intuitive approach to Svetlichny's original…

Quantum Physics · Physics 2014-10-20 Jean-Daniel Bancal , Nicolas Brunner , Nicolas Gisin , Yeong-Cherng Liang

Violation of a Bell inequality guarantees the existence of quantum correlations in a quantum state. A pure bipartite quantum state, having nonvanishing quantum correlation, always violates a Bell inequality. Such correspondence is absent…

Quantum Physics · Physics 2016-07-06 Kunal Sharma , Tamoghna Das , Aditi Sen De , Ujjwal Sen

A relationship between a recently introduced multipartite entanglement measure, state mixedness, and spin-flip symmetry is established for any finite number of qubits. It is also shown that, within those classes of states invariant under…

Quantum Physics · Physics 2009-11-10 Gregg Jaeger , Alexander V. Sergienko , Bahaa E. A. Saleh , Malvin C. Teich

Despite their importance, there is an on-going challenge characterizing multipartite quantum correlations. The Svetlichny and Mermin-Klyshko (MK) inequalities present constraints on correlations in multipartite systems, a violation of which…

Quantum Physics · Physics 2024-10-10 Rain Lenny , Dana Ben Porath , Eliahu Cohen

Quantum entanglement in multipartite systems cannot be shared freely. In order to illuminate basic rules of entanglement sharing between qubits we introduce a concept of an entangled structure (graph) such that each qubit of a multipartite…

Quantum Physics · Physics 2009-11-07 Martin Plesch , Vladimir Buzek

Local measurements acting on entangled quantum states give rise to a rich correlation structure in the multipartite scenario. We introduce a versatile technique to build families of Bell inequalities witnessing different notions of…

Quantum Physics · Physics 2019-03-27 Florian J. Curchod , Mafalda L. Almeida , Antonio Acín

We investigate quantum states that posses both maximum entanglement and maximum discord between the pertinent parties. Since entanglement (discord) is defined only for bipartite (two qubit) systems, we shall introduce an appropriate sum…

Quantum Physics · Physics 2013-03-27 J. Batle , M. Casas , A. Plastino

We present a general framework that reveals substructures of genuine multipartite entanglement. Via simple inequalities it is possible to discriminate different sets of multipartite qubit states. These inequalities are beneficial regarding…

Quantum gravity between masses can produce entangled states in thought experiments. We extend the experiments to tripartite case and construct states equivalent to Greenberger- Horne-Zeilinger states and W states under stochastic local…

Quantum Physics · Physics 2023-06-02 Shaomin Liu , Lin Chen , Mengfan Liang