English
Related papers

Related papers: General radiation states and Bell's inequalities

200 papers

We derive a Bell-type inequality for observables with arbitrary spectra. For the case of continuous variable systems we propose a possible experimental violation of this inequality, by using squeezed light and homodyne detection together…

Quantum Physics · Physics 2009-02-24 E. Shchukin W. Vogel

We report the measurement of a Bell inequality violation with a single atom and a single photon prepared in a probabilistic entangled state. This is the first demonstration of such a violation with particles of different species. The…

Quantum Physics · Physics 2008-12-03 D. L. Moehring , M. J. Madsen , B. B. Blinov , C. Monroe

A family of Bell-type inequalities is present, which are constructed directly from the "standard" Bell inequalities involving two dichotomic observables per site. It is shown that the inequalities are violated by all the generalized…

Quantum Physics · Physics 2007-05-23 Zeqian Chen

The correspondence principle suggests that quantum systems grow classical when large. Classical systems cannot violate Bell inequalities. Yet agents given substantial control can violate Bell inequalities proven for large-scale systems. We…

Quantum Physics · Physics 2021-02-10 Adam Bene Watts , Nicole Yunger Halpern , Aram Harrow

We explore the challenges posed by the violation of Bell-like inequalities by $d$-dimensional systems exposed to imperfect state-preparation and measurement settings. We address, in particular, the limit of high-dimensional systems,…

We show that correlations inconsistent with any locally causal description can be a generic feature of measurements on entangled quantum states. Specifically, spatially-separated parties who perform local measurements on a…

Quantum Physics · Physics 2016-09-08 Yeong-Cherng Liang , Nicholas Harrigan , Stephen D. Bartlett , Terry Rudolph

The problem of characterizing classical and quantum correlations in networks is considered. Contrary to the usual Bell scenario, where distant observers share a physical system emitted by one common source, a network features several…

Quantum Physics · Physics 2021-04-21 Armin Tavakoli , Marc-Olivier Renou , Nicolas Gisin , Nicolas Brunner

For a system composed of two particles Bell's theorem asserts that averages of physical quantities determined from local variables must conform to a family of inequalities. In this work we show that a classical model containing a local…

Quantum Physics · Physics 2008-06-22 A. Matzkin

We consider the entanglement of orthogonal generalized Bernoulli states in two separate single-mode high-$Q$ cavities. The expectation values and the correlations of the electric field in the cavities are obtained. We then define, in each…

Quantum Physics · Physics 2009-11-11 R. Lo Franco , G. Compagno , A. Messina , A. Napoli

Bell's theorem is typically understood as the proof that quantum theory is incompatible with local-hidden-variable models. More generally, we can see the violation of a Bell inequality as witnessing the impossibility of explaining quantum…

It is one of the most remarkable features of quantum physics that measurements on spatially separated systems cannot always be described by a locally causal theory. In such a theory, the outcomes of local measurements are determined in…

Quantum Physics · Physics 2016-09-08 Yeong-Cherng Liang

We derive tight Bell's inequalities for N>2 observers involving more than two alternative measurement settings. We give a necessary and sufficient condition for a general quantum state to violate the new inequalities. The inequalities are…

Quantum Physics · Physics 2009-11-10 Wieslaw Laskowski , Tomasz Paterek , Marek Zukowski , Caslav Brukner

For linear combinations of quantum product averages in an arbitrary bipartite state, we derive new quantum Bell-form and CHSH-form inequalities with the right-hand sides expressed in terms of a bipartite state. This allows us to specify in…

Quantum Physics · Physics 2011-01-04 Elena R. Loubenets

Bell inequalities are a consequence of measurement incompatibility (not, as generally thought, of nonlocality). In classical terms, this is equivalent to contextuality -- measurement devices do have a significant effect. Contextual models…

Quantum Physics · Physics 2007-05-23 Peter Morgan

The logical foundations of Bell's inequality are reexamined. We argue that the form of the reality condition that underpins Bell's inequality comes from the requirement of solving the quantum measurement problem. Hence any violation of…

Quantum Physics · Physics 2008-02-19 John V. Corbett , Dipankar Home

We report Bell violations with classical light prepared in both entangled and non-entangled polarization-path, binary states. Our results show that violations of constraints such as the Bell-Clauser-Horn-Shimony-Holt inequality do not…

Quantum Physics · Physics 2020-01-17 J. Gonzales , P. Sanchez , V. Avalos , F. De Zela

We investigate the non-local properties of graph states. To this aim, we derive a family of Bell inequalities which require three measurement settings for each party and are maximally violated by graph states. In turn, for each graph state…

Quantum Physics · Physics 2007-05-23 Otfried Guehne , Geza Toth , Philipp Hyllus , Hans J. Briegel

We provide a method to describe quantum nonlocality for $n$-qubit systems. By treating the correlation function as an $n$-index tensor, we derive a generalized Bell inequality. Taking generalized Greenberger-Horne-Zeilinger (GHZ) state for…

Quantum Physics · Physics 2021-05-11 Dong Ding , Yingqiu He , Fengli Yan , Ting Gao

Bell inequalities bound the strength of classical correlations between observers measuring on a shared physical system. However, studies of physical correlations can be considered beyond the standard Bell scenario by networks of observers…

Quantum Physics · Physics 2017-08-29 Armin Tavakoli

A new operator based condition for distinguishing classical from non-classical states of quantised radiation is developed. It exploits the fact that the normal ordering rule of correspondence to go from classical to quantum dynamical…

Quantum Physics · Physics 2008-11-26 Arvind , N. Mukunda , R. Simon