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Related papers: Violating Bell Inequalities Maximally for Two $d$-…

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We consider a Bell inequality for a continuous range of settings of the apparatus at each site. This "functional" Bell inequality gives a better range of violation for generalized GHZ states. Also a family of N-qubit bound entangled states…

Quantum Physics · Physics 2016-09-08 Aditi Sen De , Ujjwal Sen , Marek Zukowski

Theoretical considerations of Bell-inequality experiments usually assume identically prepared and independent pairs of particles. Here we consider pairs that exhibit both intra- and inter-pair entanglement. The pairs are taken from a large…

Quantum Physics · Physics 2009-12-17 S. Ashhab , Koji Maruyama , Caslav Brukner , Franco Nori

We introduce a permutationally invariant multipartite Bell inequality for many-body three-level systems and use it to investigate a connection between Bell nonlocality and (lack of) quantum chaos. An associated Bell operator is then defined…

Quantum Physics · Physics 2026-04-08 Albert Aloy , Guillem Müller-Rigat , Maciej Lewenstein , Jordi Tura , Matteo Fadel

Two overlapping bipartite binary input Bell inequalities cannot be simultaneously violated as this would contradict the usual no-signalling principle. This property is known as monogamy of Bell inequality violations and generally Bell…

Quantum Physics · Physics 2018-09-12 Ravishankar Ramanathan , Piotr Mironowicz

We introduce the general class of symmetric two-qubit states guaranteeing the perfect correlation or anticorrelation of Alice and Bob outcomes whenever some spin observable is measured at both sites. We prove that, for all states from this…

Quantum Physics · Physics 2019-11-19 Andrei Y. Khrennikov , Elena R. Loubenets

We analyze the correlation structure of bipartite arbitrary-dimensional Bell inequalities via novel conditions of correlations in terms of differences of joint probabilities called correlators. The conditions of correlations are shown to be…

Quantum Physics · Physics 2007-09-25 Che-Ming Li , Der-San Chuu , Yueh-Nan Chen

Bounds on the norm of quantum operators associated with classical Bell-type inequalities can be derived from their maximal eigenvalues. This quantitative method enables detailed predictions of the maximal violations of Bell-type…

Quantum Physics · Physics 2007-05-23 Stefan Filipp , Karl Svozil

The standard Bell inequality experiments test for violation of local realism by repeatedly making local measurements on individual copies of an entangled quantum state. Here we investigate the possibility of increasing the violation of a…

Quantum Physics · Physics 2007-05-23 Yeong-Cherng Liang , Andrew C. Doherty

For many decades the word "entanglement" has been firmly attached to the world of quantum mechanics, as is the phrase "Bell violation". Here we introduce Shimony-Wolf fields, entirely classical non-deterministic states, as a basis for…

Quantum Physics · Physics 2015-09-12 X. F. Qian , B. Little , J. C. Howell , J. H. Eberly

Source independent quantum networks are considered as a natural generalization to the Bell scenario where we investigate the nonlocal properties of quantum states distributed and measured in a network. Considering the simplest network of…

Quantum Physics · Physics 2020-12-30 Amit Kundu , Mostak Kamal Molla , Indrani Chattopadhyay , Debasis Sarkar

We investigate theoretically the conditions under which a multi-mode nanomechanical resonator, operated as a purely mechanical parametric oscillator, can be driven into highly nonclassical states. We find that when the device can be cooled…

Quantum Physics · Physics 2014-12-03 J. Robert Johansson , Neill Lambert , Imran Mahboob , Hiroshi Yamaguchi , Franco Nori

The relation between the boolean functions and Bell inequalities for qubits is analyzed. The connection between the maximal quantum violation of a Bell inequality and the nonlinearity of the corresponding boolean function is discussed. A…

Quantum Physics · Physics 2007-05-23 E. Shchukin

In some off-resonant cases, the reduced density matrix of two atoms symmetrically coupled with an optical cavity can very approximately approach to maximally entangled mixed states or maximal Bell violation mixed states in their evolution.…

Quantum Physics · Physics 2015-06-26 Shang-Bin Li , Jing-Bo Xu

Signals of entanglement and nonlocality are quantitatively evaluated at zero and finite temperature in an analogue black hole realized in the flow of a quasi one-dimensional Bose-Einstein condensate. The violation of Lorentz invariance…

Quantum Physics · Physics 2025-10-13 Giorgio Ciliberto , Stephanie Emig , Nicolas Pavloff , Mathieu Isoard

I derive separability inequalities for Bell correlations of observables in arbitrary pure or mixed $N$ Qudit states in $D^N$-dimensional state space. I find states (a continuum of states if $D>3$) including maximally entangled states which…

Quantum Physics · Physics 2020-02-03 S. M. Roy

The `Schr\"odinger's cat' thought experiment highlights the counterintuitive facet of quantum theory that entanglement can exist between microscopic and macroscopic systems, producing a superposition of distinguishable states like the…

Combining recent advances in superconducting quantum hardware, we explore quantum correlations in a previously inaccessible regime by observing \emph{simultaneously} high-dimensional and many-body Bell non-locality. We report a…

Quantum Physics · Physics 2026-04-28 Yousef Mafi , Ali G. Moghaddam , Teemu Ojanen

The violation of Bell inequality not only provides the most radical departure of quantum theory from classical concepts, but also paves the way of applications in such as device independent randomness certification. Here, we derive the…

Quantum Physics · Physics 2023-05-24 Youwang Xiao , Xinhui Li , Jing Wang , Ming Li , Shao-Ming Fei

We investigate quantum correlations appearing for two qubit detectors which are initially uncorrelated and locally coupled to a massless scalar field in a vacuum state. Under the perturbation up to the second order in the coupling, the…

Quantum Physics · Physics 2020-11-09 Akira Matsumura , Yasusada Nambu

Violation of Bell's inequality has been the mainspring for secure key generation in an entanglement assisted Quantum Key Distribution(QKD) protocol. Various contributions have relied on the violation of appropriate Bell inequalities to…

Quantum Physics · Physics 2023-04-19 Kaushiki Mukherjee , Tapaswini Patro , Nirman Ganguly