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Related papers: Bell's Inequality and Entanglement in Qubits

200 papers

We have determined numerically the maximum quantum violation of over 100 tight bipartite Bell inequalities with two-outcome measurements by each party on systems of up to four dimensional Hilbert spaces. We have found several cases,…

Quantum Physics · Physics 2009-11-13 K. F. Pál , T. Vértesi

We investigate the maximal violation of Bell inequalities for two $d$-dimensional systems by using the method of Bell operator. The maximal violation corresponds to the maximal eigenvalue of the Bell operator matrix. The eigenvectors…

Quantum Physics · Physics 2009-11-11 Jing-Ling Chen , Chunfeng Wu , L. C. Kwek , C. H. Oh , Mo-Lin Ge

Graph states represent a significant class of multi-partite entangled quantum states with applications in quantum error correction, quantum communication, and quantum computation. In this work, we introduce a novel formalism called the…

Quantum Physics · Physics 2025-07-16 Sameer Sharma

The inference of entangled quantum states by recourse to the maximum entropy principle is considered in connection with the recently pointed out problem of fake inferred entanglement [R. Horodecki, {\it et al.}, Phys. Rev. A {\it 59} (1999)…

Quantum Physics · Physics 2009-11-07 J. Batle , M. Casas , A. R. Plastino , A. Plastino

We numerically investigate entropic Bell inequalities for a pair of entangled qutrits using information-theoretic distances. We show that for this class of inequalities Tsallis entropy is more suitable than Shannon as it reveals…

Quantum Physics · Physics 2015-06-23 Marek Wajs , Pawel Kurzynski , Dagomir Kaszlikowski

We replace a Hamiltonian with a modular Hamiltonian in the spectral form factor and the level spacing distribution function. This study establishes a connection between quantities within Quantum Entanglement and Quantum Chaos. To have a…

High Energy Physics - Theory · Physics 2022-11-15 Chen-Te Ma , Chih-Hung Wu

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

Homogenization proposed in [Y.-C Wu and M. \.Zukowski, Phys. Rev. A 85, 022119 (2012)] is a procedure to transform a tight Bell inequality with partial correlations into a full-correlation form that is also tight. In this paper, we check…

Quantum Physics · Physics 2015-01-09 Xu Chen , Hong-Yi Su , Zhen-Peng Xu , Yu-Chun Wu , Jing-Ling Chen

The number of steps required in order to maximize a Bell inequality for arbitrary number of qubits is shown to grow exponentially with either the number of steps and the number of parties involved. The proof that the optimization of such…

Quantum Physics · Physics 2015-03-03 J. Batle , C. H. Raymond Ooi

We explore the link between two concepts: the level of violation of a Bell inequality by a quantum state and discrimination between two states by means of restricted classes of operations, such as local operations and classical…

Quantum Physics · Physics 2015-07-15 Karol Horodecki , Gláucia Murta

We compare the polynomial invariants for four qubits introduced by Luque and Thibon, PRA {\bf 67}, 042303 (2003), with optimized Bell inequalities and a combination of two qubit concurrences. It is shown for various parameter dependent…

Quantum Physics · Physics 2007-05-23 Jochen Endrejat , Helmut Buettner

We provide a novel criterion for identifying quantum correlation, which allows us to find connections between Bell type inequalities, entanglement detection, and correlation. We utilize the criterion to construct witness operators that can…

Quantum Physics · Physics 2007-05-23 Che-Ming Li , Li-Yi Hsu , Wei-Yang Lin , Yueh-Nan Chen , Der-San Chuu , Tobias Brandes

Bound entanglement, being entangled yet not distillable, is essential to our understandings of the relations between nonlocality and entanglement besides its applications in certain quantum information tasks. Recently, bound entangled…

Quantum Physics · Physics 2017-03-22 Sixia Yu , C. H. Oh

We discuss general Bell inequalities for bipartite and multipartite systems, emphasizing the connection with convex geometry on the mathematical side, and the communication aspects on the physical side. Known results on families of…

Quantum Physics · Physics 2007-05-23 Reinhard F. Werner , Michael M. Wolf

A contemporary technological milestone is to build a quantum device performing a computational task beyond the capability of any classical computer, an achievement known as quantum adversarial advantage. In what ways can the entanglement…

Quantum Physics · Physics 2020-02-05 Jacob D. Biamonte , Mauro E. S. Morales , Dax Enshan Koh

Two-qubit states occupy a large and relatively unexplored Hilbert space. Such states can be succinctly characterized by their degree of entanglement and purity. In this letter we investigate entangled mixed states and present a class of…

Quantum Physics · Physics 2009-11-07 W. J. Munro , D. F. V. James , A. G. White , P. G. Kwiat

Quantum entanglement cannot be unlimitedly shared among arbitrary number of qubits. Larger the number of entangled pairs in an N-qubit system, smaller the degree of bi-partite entanglement is. We analyze a system of N qubits in which an…

Quantum Physics · Physics 2009-11-06 Masato Koashi , Vladimir Buzek , Nobuyuki Imoto

We show that bipartite entanglements involving non-orthogonal states are {\it necessarily nonmaximally} entangled, however {\it small} the non-orthogonality may be. How the deviation from maximal entanglement is related to nonorthogonality…

Quantum Physics · Physics 2007-05-23 Dipankar Home , M K Samal

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

One of the great challenges of quantum foundations and quantum information theory is the characterisation of the relationship between entanglement and the violation of Bell inequalities. It is well known that in specific scenarios these two…

Quantum Physics · Physics 2020-04-01 Flavien Hirsch , Marcus Huber