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Related papers: High-spin measurements in an arbitrary two-qudit s…

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In terms of quantum probability statistics the Bell inequality (BI) and its violation are extended to spin-$s$ entangled Schr\"{o}dinger cat-state (called the Bell cat-state) with both parallel and antiparallel spin-polarizations. The BI is…

Quantum Physics · Physics 2022-01-04 Yan Gu , Haifeng Zhang , Zhigang Song , L. -F. Wei , J. -Q. Liang

How can we analyze quantum correlations in large and noisy systems without quantum state tomography? An established method is to measure total angular momenta and employ the so-called spin-squeezing inequalities based on their expectations…

Quantum Physics · Physics 2024-08-23 Jan Lennart Bönsel , Satoya Imai , Ye-Chao Liu , Otfried Gühne

Bell inequalities (BIs) derived in terms of quantum probability statistics are extended to general bipartite-entangled states of arbitrary spins with parallel polarization. The original formula of Bell for the two-spin singlet is slightly…

Quantum Physics · Physics 2017-02-27 Haifeng Zhang , Jianhua Wang , Zhigang Song , J. -Q. Liang , L. -F. Wei

Violation of Bell's Inequalities gives experimental evidence for the existence of a spin 1/2 which has two simultaneous axes of spin quantization rather than one. These couple to form a resonance state, called the spin fringe, and this…

General Physics · Physics 2007-10-10 B. C. Sanctuary

We model a typical Bell-test experimental situation by considering that Alice and Bob perform incompatible measurements in a sequential way, with mixed orders of execution. After emphasizing that order effects will generally produce a…

Quantum Physics · Physics 2021-04-08 Massimiliano Sassoli de Bianchi

There exist bipartite entangled states whose violations of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality can be observed by a single Alice and arbitrarily many sequential Bobs [Phys. Rev. Lett. 125, 090401 (2020)]. Here we consider its…

Quantum Physics · Physics 2023-11-08 Ya Xi Mao-Sheng Li Libin Fu , Zhu-Jun Zheng

We demonstrate an experimental test of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality which seemingly exhibits correlations beyond the limits imposed by quantum mechanics. Inspired by the idea of Fourier synthesis, we design…

Quantum Physics · Physics 2015-06-17 Jacquiline Romero , Daniel Giovannini , Daniel Tasca , Steve Barnett , Miles Padgett

In the first half of this two-part article, we analyzed a cognitive psychology experiment where participants were asked to select pairs of directions that they considered to be the best example of 'Two Different Wind Directions', and showed…

Recently, it has been shown that at most two observers (Bobs) can sequentially demonstrate bipartite nonlocality with a spatially separated single observer (Alice) invoking a scenario where an entangled system of two spin-$\frac{1}{2}$…

Quantum Physics · Physics 2019-02-07 Debarshi Das , Arkaprabha Ghosal , Souradeep Sasmal , Shiladitya Mal , A. S. Majumdar

We consider the evaluation of the quantum discord and other related measures of quantum correlations in a system formed by a spin 1 and a complementary spin system. A characterization of general projective measurements in such system in…

Quantum Physics · Physics 2015-06-05 R. Rossignoli , J. M. Matera , N. Canosa

Based on the Pauli spin operators we develop the notion of the spin-correlation matrix for the two-qubit system. If this matrix is non-zero, the measure of the correlation between the qubits is the average of the non-zero elements.…

Quantum Physics · Physics 2012-04-18 Faisal A. A. El-Orany

We describe a simple experimental setting where joint measurements performed on a single (classical or quantum) entity can violate both the Bell-CHSH inequality and the marginal laws (also called no-signaling conditions). Once emitted by a…

Quantum Physics · Physics 2021-09-09 Diederik Aerts , Massimiliano Sassoli de Bianchi

We in this paper study quantum correlations for two neutral spin-particles coupled with a single-mode optical cavity through the usual magnetic interaction. Two-spin entangled states for both antiparallel and parallel spin-polarizations are…

Quantum Physics · Physics 2017-08-02 Xue-Min Bai , Chun-Ping Gao , Jun-Qi Li , Ni Liu , J. -Q. Liang

The possibility of performing simultaneous measurements in quantum mechanics is investigated in the context of the Curie-Weiss model for a projective measurement. Concretely, we consider a spin-$\frac{1}{2}$ system simultaneously…

Quantum Physics · Physics 2017-06-01 Martí Perarnau-Llobet , Theo M. Nieuwenhuizen

We propose and implement a non-destructive measurement that distinguishes between two-electron spin states in a quantum dot. In contrast to earlier experiments with quantum dots, the spins are left behind in the state corresponding to the…

For an even qudit dimension $d\geq 2,$ we introduce a class of two-qudit states exhibiting perfect correlations/anticorrelations and prove via the generalized Gell-Mann representation that, for each two-qudit state from this class, the…

Quantum Physics · Physics 2019-10-08 Elena R. Loubenets , Andrei Y. Khrennikov

Bell-Clauser-Horne-Shimony-Holt inequality (in terms of correlation functions) of two qutrits is studied in detail by employing tritter measurements. A uniform formula for the maximum value of this inequality for tritter measurements is…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Xian-Geng Zhao

We derive bounds for the entanglement of a spin with an (adjacent and non-adjacent) interval of spins in an arbitrary pure finitely correlated state (FCS) on a chain of spins of any magnitude. Finitely correlated states are otherwise known…

Mathematical Physics · Physics 2007-05-23 Spyridon Michalakis , Bruno Nachtergaele

We study theoretically the properties of two Bose-Einstein condensates in different spin states, represented by a double Fock state. Individual measurements of the spins of the particles are performed in transverse directions, giving access…

Quantum Physics · Physics 2009-11-13 Franck Laloë , William J. Mullin

The original formula of Bell inequality (BI) in terms of two-spin singlet has to be modified for the entangled-state with parallel spin polarization. Based on classical statistics of the particle-number correlation, we prove in this paper…

Quantum Physics · Physics 2018-09-24 Yan Gu , Haifeng Zhang , Zhigang Song , J. -Q. Liang , L. -F. Wei