Cirel'son inequality states that the absolute value of the combination of quantum correlations appearing in the Clauser-Horne-Shimony-Holt (CHSH) inequality is bound by 2 square root of (2). It is shown that the correlations of two qubits belonging to a three-qubit system can violate the CHSH inequality beyond 2 square root of (2). Such a violation is not in conflict with Cirel'son's inequality because it is based on postselected systems. The maximum allowed violation of the CHSH inequality, 4, can be achieved using a Greenberger-Horne-Zeilinger state.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.88.060403 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
W-Class States-Identification and Quantification of Bell-CHSH Inequalities' Violation.
Entropy (Basel)
December 2024
Joint Laboratory of Optics of Palacký University and Institute of Physics of AS CR, Faculty of Science, Palacký University, 17. listopadu 12, 779 00 Olomouc, Czech Republic.
We discuss a family of W-class states describing three-qubit systems. For such systems, we analyze the relations between the entanglement measures and the nonlocality parameter for a two-mode mixed state related to the two-qubit subsystem. We find the conditions determining the boundary values of the negativity, parameterized by concurrence, for violating the Bell-CHSH inequality.
View Article and Find Full Text PDFUndergraduate setup for measuring the Bell inequalities and performing quantum state tomography.
EPJ Quantum Technol
December 2024
Departament de Física Quàntica i Astrofísica, Facultat de Física, Universitat de Barcelona (UB), C. Martí i Franquès, 1, 08028 Barcelona, Spain.
The growth of quantum technologies is attracting the interest of many students eager to learn concepts such as quantum entanglement or quantum superposition. However, the non-intuitive nature of these concepts poses a challenge to understanding them. Here, we present an entangled photon system which can perform a Bell test, i.
View Article and Find Full Text PDFViolation of Leggett-Garg Inequality in Perceiving Cup-like Objects and Cognitive Contextuality.
Entropy (Basel)
November 2024
School of Communication Science, Beijing Language and Culture University, Beijing 100083, China.
This paper is devoted to an experimental investigation of cognitive contextuality inspired by quantum contextuality research. This contextuality is related to, but not identical to context-sensitivity which is well-studied in cognitive psychology and decision making. This paper is a part of quantum-like modeling, i.
View Article and Find Full Text PDFArticle Synopsis
- Photon-based entanglement sources, essential for creating entangled states, often suffer from quality loss due to birefringence in nonlinear crystals during spontaneous parametric down-conversion.
- The study provides a theoretical analysis of birefringent walk-off and demonstrates that using pre- and post-compensation can improve entangled photon quality.
- Experimental validation shows significant success, achieving a violation of CHSH-Bell's inequality by about 366 standard deviations, making this method applicable to various optical quantum technologies, such as computation, sensing, and communication.
We present an experimental implementation of a polarization-entangled photon-pair source based on beam displacers. The down-converted photons are emitted via spontaneous parametric downconversion in a non-degenerate and type-0 process. We obtain a state fidelity of F = 0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!