Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Chinese Physics Letters

Quantum Nonlocality and Entanglement of Pair Cat States with Phase Decoherence

Xu Hang-Shi, Jing‐Bo Xu

Published May 1, 2008• 1 citation
Publisher

Abstract

We investigate the entanglement of pair cat states in the phase damping channel by adopting the log-negativity and then study the possible violations of Bell's inequalities for the pair cat states in terms of the Wigner representation in phase space based upon parity measurement and displacement operation.
DOI
10.1088/0256-307x/25/5/009

Related papers

Nonlocality of the Schrödinger cat

Krzysztof Wódkiewicz

The nonlocality of the Schrödinger cat is established. A correlation measurement that exhibits quantum interference in the form of the Wigner function of the cat state is introduced. The relation of this correlation to quantum interference in phase space and the nonlocal character of the Schrödinger cat are discussed. It is shown that the Schrödinger cat correlation function leads to violation of the Bell inequality for macroscopically distinguishable states of the cat.

New Journal of Physics•Sep 12, 2000•30 citations

Quantum Correlations and Bell Inequality Violation under Decoherence

Volkan Erol

Quantum Correlations are studied extensively in quantum information domain. Entanglement Measures and Quantum Discord are good examples of these actively studied correlations. Detection of violation in Bell inequalities is also a widely active area in quantum information theory world. In this work, we revisit the problem of analyzing the behavior of quantum correlations and violation of Bell inequalities in noisy channels. We extend the problem defined in [1] by observing the changes in negativity measure, quantum discord and a modified version of Horodecki measure for violation of Bell inequalities under amplitude damping, phase damping and depolarizing channels. We report different interesting results for each of these correlations and measures. All these correlations and measures decrease under decoherence channels, but some changes are very dramatical comparing to others. We investigate also separability conditions of example studied states.

arXiv:1705.03882•May 12, 2017•0 citations

Behaviour of Quantum Correlations and Violation of Bell Inequalities in some Noisy Channels

Volkan Erol

Quantum Correlations are studied extensively in quantum information domain. Entanglement Measures and Quantum Discord are good examples of these actively studied correlations. Detection of violation in Bell inequalities is also a widely active area in quantum information theory world. In this work, we revisit the problem of analyzing the behavior of quantum correlations and violation of Bell inequalities in noisy channels. We extend the problem defined in a recent study by observing the changes in negativity measure, quantum discord and a modified version of Horodecki measure for violation of Bell inequalities under amplitude damping, phase damping and depolarizing channels. We report different interesting results for each of these correlations and measures. All these correlations and measures decrease under decoherence channels, but some changes are very dramatical comparing to others. We investigate also separability conditions of example studied states.

•May 11, 2017•0 citations

Entanglement Swapping of Pair Coherent States with Phase Decoherence

Ye-Qi Zhang, Jing‐Bo Xu

We investigate the entanglement swapping of continuous variable using the pair coherent state as the input state and the two-mode squeezed vacuum which is exposed in a phase decoherence environment as the quantum channel. By adopting the log-negativity as the measure of entanglement, we analyze how entanglement of the two initial states and the phase decoherence environment affect the entanglement swapping quality.

Chinese Physics Letters•Jul 1, 2009•5 citations

Decoherence effects on the nonlocality of symmetric states

Adel Sohbi, Isabelle Zaquine, Eleni Diamanti +1 more

The observation of the nonlocal properties of multipartite entangled states is of great importance for quantum information protocols. Such properties, however, are fragile and may not be observed in the presence of decoherence exhibited by practical physical systems. In this work we investigate the robustness of the nonlocality of symmetric states experiencing phase and amplitude damping, using suitable Bell inequalities based on an extended version of Hardy's paradox. We derive thresholds for observing nonlocality in terms of experimental noise parameters and demonstrate the importance of the choice of the measurement bases for optimizing the robustness. For $W$ states, in the phase damping case, we show that this choice can lead to a trade-off between obtaining a high violation of the nonlocal test and optimal robustness thresholds; we also show that in this setting the nonlocality of $W$ states is particularly robust for a large number of qubits. Furthermore, we apply our techniques to the discrimination of symmetric states belonging to different entanglement classes, thus illustrating their usefulness for a wide range of practical quantum information applications.

arXiv:1411.4489•Physical Review A•Feb 2, 2015•27 citations

Quantum Nonlocality and Generation of Multi-mode Schrodinger Cat States

Zheng Shi-Biao

We describe the Greenberger–Horne–Zeilinger (GHZ) paradox in the multi-mode Schrödinger cat states. We also show that the multi-mode cat states violate the Bell's inequality by an amount that grows exponentially with number of modes. The test of quantum nonlocality is based on parity measurement and displacement operation, which are experimentally feasible. We also describe a scheme for the generation of the cat states in cavity QED.

Communications in Theoretical Physics•Oct 15, 2004•3 citations
Quantum Correlations are studied extensively in quantum information domain. Entanglement Measures and Quantum Discord are good examples of these actively studied correlations. Detection of violation in Bell inequalities is also a widely active area in quantum information theory world. In this work, we revisit the problem of analyzing the behavior of quantum correlations and violation of Bell inequalities in noisy channels. We extend the problem defined in [1] by observing the changes in negativity measure, quantum discord and a modified version of Horodecki measure for violation of Bell inequalities under amplitude damping, phase damping and depolarizing channels. We report different interesting results for each of these correlations and measures. All these correlations and measures decrease under decoherence channels, but some changes are very dramatical comparing to others. We investigate also separability conditions of example studied states.
Quantum Correlations are studied extensively in quantum information domain. Entanglement Measures and Quantum Discord are good examples of these actively studied correlations. Detection of violation in Bell inequalities is also a widely active area in quantum information theory world. In this work, we revisit the problem of analyzing the behavior of quantum correlations and violation of Bell inequalities in noisy channels. We extend the problem defined in a recent study by observing the changes in negativity measure, quantum discord and a modified version of Horodecki measure for violation of Bell inequalities under amplitude damping, phase damping and depolarizing channels. We report different interesting results for each of these correlations and measures. All these correlations and measures decrease under decoherence channels, but some changes are very dramatical comparing to others. We investigate also separability conditions of example studied states.
The observation of the nonlocal properties of multipartite entangled states is of great importance for quantum information protocols. Such properties, however, are fragile and may not be observed in the presence of decoherence exhibited by practical physical systems. In this work we investigate the robustness of the nonlocality of symmetric states experiencing phase and amplitude damping, using suitable Bell inequalities based on an extended version of Hardy's paradox. We derive thresholds for observing nonlocality in terms of experimental noise parameters and demonstrate the importance of the choice of the measurement bases for optimizing the robustness. For WWW states, in the phase damping case, we show that this choice can lead to a trade-off between obtaining a high violation of the nonlocal test and optimal robustness thresholds; we also show that in this setting the nonlocality of WWW states is particularly robust for a large number of qubits. Furthermore, we apply our techniques to the discrimination of symmetric states belonging to different entanglement classes, thus illustrating their usefulness for a wide range of practical quantum information applications.