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Related papers: Entanglement criteria and nonlocality for multi-mo…

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We explore the effect of two-dimensional position-space non-commutativity on the bipartite entanglement of continuous variable systems. We first extend the standard symplectic framework for studying entanglement of Gaussian states of…

Quantum Physics · Physics 2013-05-29 S. Adhikari , B. Chakraborty , A. S. Majumdar , S. Vaidya

Entanglement and nonlocality are both fundamental aspects of quantum theory, and play a prominent role in quantum information science. The exact relation between entanglement and nonlocality is however still poorly understood. Here we make…

Quantum Physics · Physics 2012-01-24 Tamas Vertesi , Nicolas Brunner

We prove that every conceivable hidden variable model reproducing the quantum mechanical predictions of almost any entangled state must necessarily violate Bell's locality condition. The proof does not involve the consideration of any Bell…

Quantum Physics · Physics 2007-05-23 GianCarlo Ghirardi , Luca Marinatto

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

Quantum entanglement and nonlocality are foundational to quantum technologies, driving quantum computation, communication, and cryptography innovations. To benchmark the capabilities of these quantum techniques, efficient detection and…

Quantum Physics · Physics 2024-12-03 Zhuo Chen , Fei Shi , Qi Zhao

In this Letter, we show that the fulfillment of uncertainty relations is a sufficient criterion for a quantum-mechanically permissible state. We specifically construct two pseudo-spin observables for an arbitrary non-positive Hermitian…

Quantum Physics · Physics 2009-11-13 Hyunchul Nha , M. Suhail Zubairy

We review some counterintuitive properties of standard measures describing quantum entanglement and violation of Bell's inequality (often referred to as "nonlocality") in two-qubit systems. By comparing the nonlocality, negativity,…

Quantum Physics · Physics 2020-01-10 Adam Miranowicz , Bohdan Horst , Andrzej Koper

A 3-setting Bell-type inequality enforced by the indeterminacy relation of complementary local observables is proposed as an experimental test of the 2-qubit entanglement. The proposed inequality has an advantage of being a sufficient and…

Quantum Physics · Physics 2016-11-15 Sixia Yu , Jian-Wei Pan , Zeng-Bing Chen , Yong-De Zhang

Detection and quantification of entanglement in quantum resources are two key steps in the implementation of various quantum-information processing tasks. Here, we show that Bell-type inequalities are not only useful in verifying the…

Quantum Physics · Physics 2011-02-28 Yeong-Cherng Liang , Tamas Vertesi , Nicolas Brunner

We investigate the connection between entanglement and non-locality between continuous-variable bipartite Gaussian states. The investigation initiates with formulating non-locality by using the phase-space Wigner representation of Bell's…

Quantum Physics · Physics 2025-07-31 Souvik Agasti

We consider entanglement detection for quantum key distribution systems that use two signal states and continuous variable measurements. This problem can be formulated as a separability problem in a qubit-mode system. To verify…

Quantum Physics · Physics 2007-05-23 Johannes Rigas , Otfried Gühne , Norbert Lütkenhaus

Entanglement is one of the most studied properties of quantum mechanics for its application in quantum information protocols. Nevertheless, detecting the presence of entanglement in large multipartite sates continues to be a great challenge…

Quantum Physics · Physics 2017-06-21 Flavio Baccari , Daniel Cavalcanti , Peter Wittek , Antonio Acín

We demonstrate genuine three-mode nonlocality based on phase space formalism. A Svetlichny-type Bell inequality is formulated in terms of the $s$-parameterized quasiprobability function. We test such tool using exemplary forms of three-mode…

Quantum Physics · Physics 2015-06-12 Seung-Woo Lee , Mauro Paternostro , Jinhyoung Lee , Hyunseok Jeong

We study the detection of continuous-variable entanglement, for which most of the existing methods designed so far require a full specification of the devices, and we present protocols for entanglement detection in a scenario where the…

Quantum Physics · Physics 2021-05-19 Paolo Abiuso , Stefan Bäuml , Daniel Cavalcanti , Antonio Acín

We provide a method to construct entanglement criteria for arbitrary multipartite systems of discrete or continuous variables and hybrid combinations of both. While any set of local operators generates a sufficient condition for…

Quantum Physics · Physics 2016-08-09 Manuel Gessner , Luca Pezzè , Augusto Smerzi

We introduce two entanglement conditions that take the form of inequalities involving expectation values of operators. These conditions are sufficient conditions for entanglement, that is if they are satisfied the state is entangled, but if…

Quantum Physics · Physics 2015-05-19 Mark Hillery , Ho Trung Dung , Hongjun Zheng

In a multipartite setting, it is possible to distinguish quantum states that are genuinely $n$-way entangled from those that are separable with respect to some bipartition. Similarly, the nonlocal correlations that can arise from…

Quantum Physics · Physics 2013-07-24 Jean-Daniel Bancal , Jonathan Barrett , Nicolas Gisin , Stefano Pironio

EPR showed that two particles emitted from a source can be entangled by a shared wavefunction where two non-commuting observables (position, momentum) can be simultaneously real, leading to a contradiction with quantum mechanics (two…

Quantum Physics · Physics 2026-03-12 Mafiz Uddin

While all bipartite pure entangled states are known to generate correlations violating a Bell inequality, and are therefore nonlocal, the quantitative relation between pure-state entanglement and nonlocality is poorly understood. In fact,…

Quantum Physics · Physics 2018-08-14 Victoria Lipinska , Florian Curchod , Alejandro Máttar , Antonio Acín

Understanding the relation between nonlocality and entanglement is one of the fundamental problems in quantum physics. In the bipartite case, it is known that the correlations observed for some entangled quantum states can be explained…

Quantum Physics · Physics 2015-07-22 R. Augusiak , M. Demianowicz , J. Tura , A. Acín