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Related papers: CHSH violation and entropy - concurrence plane

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We present a reliable algorithm to evaluate quantum discord for general two--qubit states, amending and extending an approach recently put forward for the subclass of X--states. A closed expression for the discord of arbitrary states of two…

Quantum Physics · Physics 2011-05-23 Davide Girolami , Gerardo Adesso

We present numerical data showing, that three qutrit correlations for a pure state, which is not maximally entangled, violate local realism more strongly than three-qubit correlations. The strength of violation is measured by the minimal…

Quantum Physics · Physics 2007-05-23 Dagomir Kaszlikowski , Darwin Gosal , E. J. Ling , L. C. Kwek , Marek Zukowski , C. H. Oh

We describe a protocol for generating random numbers based on the existence of quantum violations of a free Clauser-Horne-Shimony-Holt inequality, namely CHSH-3. Our method uses semidefinite programming relaxations to compute such…

Quantum Physics · Physics 2020-07-31 Don Jean Baptiste Anoman , François Arnault , Simone Naldi

Among the many facets of quantum correlations, bound entanglement has remained one the most enigmatic phenomena, despite the fact that it was discovered in the early days of quantum information. Even its detection has proven to be…

Quantum Physics · Physics 2016-09-07 Gael Sentís , Christopher Eltschka , Jens Siewert

Criteria of measure quantifying quantum coherence, a unique property of quantum system, are proposed recently. In this paper, we first give an uncertainty-like expression relating the coherence and the entropy of quantum system. This…

Quantum Physics · Physics 2015-07-15 Zhengjun Xi , Yongming Li , Heng Fan

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

A scheme for generating the maximally entangled mixed state of two atoms on-resonance asymmetrically coupled to a single mode optical cavity field is presented. The part frontier of both maximally entangled mixed states and maximal Bell…

Quantum Physics · Physics 2009-11-13 Shang-Bin Li

A set of Bell inequalities classifying the quantum entanglement of four-qubit states is presented. These inequalities involve only two measurement settings per observer and can characterize fully separable, bi-separable and tri-separable…

Quantum Physics · Physics 2013-07-26 Hui Zhao , Xing-Hua Zhang , Shao-Ming Fei , Zhi-Xi Wang

The violation of the Bell-CHSH inequality for bipartite systems is discussed by making use of the pseudospin operators which enable us to group all modes of the Hilbert space of the system in pairs. We point out that a single pair can be…

Quantum Physics · Physics 2024-01-29 Silvio Paolo Sorella

A scheme for generating an entangled state in a two spin-1/2 system by means of a spin-dependent potential scattering of another qubit is presented and analyzed in three dimensions. The entanglement is evaluated in terms of the concurrence…

Quantum Physics · Physics 2010-04-07 Yuichiro Hida , Hiromichi Nakazato , Kazuya Yuasa , Yasser Omar

We consider quantum systems composed of $N$ qubits, and the family of all Bell's correlation inequalities for two two-valued measurements per site. We show that if a $N$-qubit state $\rho$ violates any of these inequalities, then it is at…

Quantum Physics · Physics 2009-11-07 A. Acin , V. Scarani , M. M. Wolf

We construct quantum gate entanglers for different classes of multipartite states based on definition of W and GHZ concurrence classes. First, we review the basic construction of concurrence classes based on orthogonal complement of a…

Quantum Physics · Physics 2015-05-18 Hoshang Heydari

Bell-inequality violations establish that two systems share some quantum entanglement. We give a simple test to certify that two systems share an asymptotically large amount of entanglement, n EPR states. The test is efficient: unlike…

Quantum Physics · Physics 2018-09-06 Rui Chao , Ben W. Reichardt , Chris Sutherland , Thomas Vidick

We computationally investigate the complete polytope of Bell inequalities for 2 particles with small numbers of possible measurements and outcomes. Our approach is limited by Pitowsky's connection of this problem to the computationally hard…

Quantum Physics · Physics 2023-03-23 Daniel Collins , Nicolas Gisin

Incompatibility and nonlocality are not only of foundational interest but also act as important resources for quantum information theory. In the Clauser-Horne-Shimony-Holt (CHSH) scenario, the incompatibility of a pair of observables is…

Quantum Physics · Physics 2023-02-21 Swati Kumari , Javid Naikoo , Sibasish Ghosh , A. K. Pan

We introduce an entanglement-related quantity that we call the binegativity. Based on numerical evidence, we conjecture that the binegativity is an entanglement measure for two-qubit states. The binegativity is compared to the concurrence…

Quantum Physics · Physics 2017-02-13 Mark W. Girard , Gilad Gour

Recently Munro, Nemoto and White (The Bell Inequality: A measure of Entanglement?, quant-ph/0102119) tried to indicate that the reason behind a state rho having higher amount of entanglement (as quantified by the entanglement of formation)…

Quantum Physics · Physics 2009-11-07 Sibasish Ghosh , Guruprasad Kar , Aditi Sen De , Ujjwal Sen

Entanglement is one of the key resources required for quantum computation, so experimentally creating and measuring entangled states is of crucial importance in the various physical implementations of a quantum computer. In superconducting…

Recently, the fast development of quantum technologies led to the need for tools allowing the characterization of quantum resources. In particular, the ability to estimate non-classical aspects, e.g. entanglement and quantum discord, in…

We study a class of Bell inequalities and find their maximum quantum violation. These inequalities involve n parties, two measurements per party, with each measurement having two outcomes. The n=2 case corresponds to the CH inequality. We…

Quantum Physics · Physics 2013-05-30 V. Ugur Guney , Mark Hillery