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Related papers: Scalable Bell inequalities for multiqubit systems

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Bipartite Bell inequalities can be simultaneously violated by two different pairs of observers when weak measurements and signaling is employed. Here we experimentally demonstrate the violation of two simultaneous CHSH inequalities by…

Quantum Physics · Physics 2017-04-10 Matteo Schiavon , Luca Calderaro , Mirko Pittaluga , Giuseppe Vallone , Paolo Villoresi

One fascinating way of revealing the quantum nonlocality is the all-versus-nothing test due to Greenberger, Horne, and Zeilinger (GHZ) known as GHZ paradox. So far genuine multipartite and multilevel GHZ paradoxes are known to exist only in…

Quantum Physics · Physics 2013-03-22 Weidong Tang , Sixia Yu , C. H. Oh

A violation of Bell local realism inequalities in Clauser-Horn-Shimony-Holt (CHSH) form has been discovered in a relativistic GedanknExperiment. This means that there are no definite joint probabilities and this finds a classical…

General Physics · Physics 2024-06-03 Alexander Belinsky , Igor Dzhadan

Distinct from the type of local realist inequality (known as the Collins-Gisin-Linden-Massar-Popescu or CGLMP inequality) usually used for bipartite qutrit systems, we formulate a new set of local realist inequalities for bipartite qutrits…

Quantum Physics · Physics 2017-09-18 Debarshi Das , Shounak Datta , Suchetana Goswami , A. S. Majumdar , Dipankar Home

The violation of Bell inequalities where both detection and locality loopholes are closed is crucial for device independent assessments of quantum information. While of technological nature, the simultaneous closing of both loopholes still…

Quantum Physics · Physics 2015-06-17 Colin Teo , Jiří Minář , Daniel Cavalcanti , Valerio Scarani

The distribution of high-quality Greenberger-Horne-Zeilinger (GHZ) states is at the heart of many quantum communication tasks, ranging from extending the baseline of telescopes to secret sharing. They also play an important role in…

Quantum Physics · Physics 2021-11-02 Sébastian de Bone , Runsheng Ouyang , Kenneth Goodenough , David Elkouss

The connection between quantum optical nonclassicality and the violation of Bell's inequalities is explored. Bell type inequalities for the electromagnetic field are formulated for general states of quantised radiation and their violation…

Quantum Physics · Physics 2009-10-31 Arvind , N. Mukunda

A correlation inequality is derived from local realism and a supplementary assumption. Unlike Clauser-Horne (CH) inequality [or Clauser-Horne-Shimony-Holt (CHSH) inequality] which is violated by quantum mechanics by a factor of $\sqrt 2$,…

Quantum Physics · Physics 2007-05-23 M. Ardehali

Bell inequalities can be studied both as constraints in the space of probability distributions and as expectation values of multipartite operators. The latter approach is particularly useful when considering outcomes as eigenvalues of…

Quantum Physics · Physics 2016-09-22 Daniel Alsina , Alba Cervera , Dardo Goyeneche , José I. Latorre , Karol Życzkowski

Wigner's argument inferring Bell-type inequality for the EPR-Bohm entangled state is generalized here for any N-partite state. This is based on assuming for the relevant dichotomic observables the existence of the overall joint probability…

Quantum Physics · Physics 2016-11-18 Dipankar Home , Debashis Saha , Siddhartha Das

While Bell nonlocality of a bipartite system is counter-intuitive, multipartite nonlocality in our many-body world turns out to be even more so. Recent theoretical study reveals in a theory-agnostic manner that genuine multipartite nonlocal…

Quantum Physics · Physics 2022-10-19 Ya-Li Mao , Zheng-Da Li , Sixia Yu , Jingyun Fan

Optical hybrid entanglement can be created between two qubits, one encoded in a single photon and another one in coherent states with opposite phases. It opens the path to a variety of quantum technologies, such as heterogeneous quantum…

We have determined numerically the maximum quantum violation of over 100 tight bipartite Bell inequalities with two-outcome measurements by each party on systems of up to four dimensional Hilbert spaces. We have found several cases,…

Quantum Physics · Physics 2009-11-13 K. F. Pál , T. Vértesi

We present a Theorem that all generalized Greenberger-Horne-Zeilinger states of a three-qubit system violate a Bell inequality in terms of probabilities. All pure entangled states of a three-qubit system are shown to violate a Bell…

Quantum Physics · Physics 2009-11-10 Jing-Ling Chen , Chunfeng Wu , L. C. Kwek , C. H. Oh

Violation of the Bell-type inequalities is necessary to confirm the existence of nonlocality in nonclassical (entangled) states. We have designed a customized operator which is made of the sum of the Pauli matrices ($\sigma_x$, $\sigma_y$,…

Quantum Physics · Physics 2025-09-30 Tomis Prajapati , Harsh Mehta , Shreya Banerjee , Prasanta K. Panigrahi , V. Narayanan

Which nonlocal correlations can be obtained, when a party has access to more than one subsystem? While traditionally nonlocality deals with spacelike separated parties, this question becomes important with quantum technologies that connect…

Quantum Physics · Physics 2023-09-04 Moisés Bermejo Morán , Alejandro Pozas-Kerstjens , Felix Huber

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 investigate the robustness of multiparty nonlocality under local decoherence, acting independently and equally on each subsystems. To be specific, we consider an N-qubit GHZ state under depolarization, dephasing, or dissipation channel,…

Quantum Physics · Physics 2013-05-29 Sung Soon Jang , Yong Wook Cheong , Jaewan Kim , Hai-Woong Lee

We present a set of Bell inequalities that gives rise to a finer classification of the entanglement for tripartite systems. These inequalities distinguish three possible bi-separable entanglements for three-qubit states. The three Bell…

Quantum Physics · Physics 2007-05-23 Bao-Zhi Sun , Shao-Ming Fei

Bell-type inequalities and violations thereof reveal the fundamental differences between standard probability theory and its quantum counterpart. In the course of previous investigations ultimate bounds on quantum mechanical violations have…

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