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Related papers: Recycling nonlocality in a quantum network

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Quantum nonlocality is arguably among the most counter-intuitive phenomena predicted by quantum theory. In recent years, the development of an abstract theory of nonlocality has brought a much deeper understanding of the subject. In…

By using photon pairs created in parametric down conversion, we report on an experiment, which demonstrates that measurement can recover the quantum entanglement of two qubit system in a pure dephasing environment. The concurrence of the…

Quantum Physics · Physics 2010-12-22 Xiao-Ye Xu , Jin-Shi Xu , Chuan-Feng Li , Guang-Can Guo

Quantum entanglement and nonlocality are inextricably linked. However, while entanglement is necessary for nonlocality, it is not always sufficient in the standard Bell scenario. We derive sufficient conditions for entanglement to give rise…

Quantum Physics · Physics 2021-02-22 Patricia Contreras-Tejada , Carlos Palazuelos , Julio I. de Vicente

It is a well-known fact that measurement incompatibility is a necessary resource to generate nonlocal correlations in usual Bell scenario that typically involves single quantum source. We can provide with some contrasting findings if we…

Quantum Physics · Physics 2025-08-15 Kaushiki Mukherjee , Biswajit Paul

Bell nonlocality is the key quantum resource in some device-independent quantum information processing. It is of great importance to study the efficient sharing of this resource. Unsharp measurements are widely used in sharing the…

Quantum Physics · Physics 2024-02-21 Tinggui Zhang , Hong Yang , Shao-Ming Fei

Quantum nonlocality can be demonstrated without inputs (i.e. each party using a fixed measurement setting) in a network with independent sources. Here we consider this effect on ring networks, and show that the underlying quantum strategy…

Quantum Physics · Physics 2025-02-11 Pavel Sekatski , Sadra Boreiri , Nicolas Brunner

Quantum nonlocality offers a secure way to produce random numbers: their unpredictability is intrinsic and can be certified just by observing the statistic of the measurement outcomes, without assumptions on how they are produced. To do…

Quantum correlations in networks with independent sources have revealed novel forms of nonclassical behavior. While entanglement in the sources is a necessary ingredient, the role played by entanglement in the measurements remains largely…

Entanglement and Bell nonlocality are used to describe quantum inseparabilities. Bell-nonlocal states form a strict subset of entangled states. A natural question arises concerning how much territory Bell nonlocality occupies entanglement…

Quantum Physics · Physics 2019-09-04 Xiao-Gang Fan , Zhi-Yong Ding , Fei Ming , Huan Yang , Dong Wang , Liu Ye

Networks composed of independent sources of entangled particles that connect distant users are a rapidly developing quantum technology and an increasingly promising test-bed for fundamental physics. Here we address the certification of…

In a quantum network, distant observers sharing physical resources emitted by independent sources can establish strong correlations, which defy any classical explanation in terms of local variables. We discuss the characterization of…

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

Many three-party correlations, including some that are commonly described as genuinely tripartite nonlocal, can be simulated by a network of underlying subsystems that display only bipartite nonsignaling nonlocal behavior. Quantum mechanics…

Quantum Physics · Physics 2021-07-19 Peter Bierhorst

Quantum nonlocality as a witness of entanglement plays a crucial role in various fields. Existing quantum monogamy relations rule out the possibility of simultaneous violations of any Bell inequalities with partial statistics generated from…

Quantum Physics · Physics 2024-03-15 Yan-Han Yang , Xin-Zhu Liu , Xing-Zhou Zheng , Shao-Ming Fei , Ming-Xing Luo

The characterization of quantum correlations in terms of information-theoretic resource has been a fruitful approach to understand the power of quantum correlations as a resource. While bipartite entanglement and Bell inequality violation…

Quantum Physics · Physics 2014-11-27 Florian Curchod , Yeong-Cherng Liang , Nicolas Gisin

One of the most fascinating aspects of quantum networks is their capability to distribute entanglement as a nonlocal communication resource. In a first step, this requires network-ready devices that can generate and store entangled states.…

We argue that the conclusion of Bell theorem, namely, that there must be spatial non-local correlations in certain experimental situations, does not apply to typical individual measurements performed on entangled EPR pairs. Our claim is…

General Physics · Physics 2015-10-22 Victor Romero-Rochin

Quantum networks allow in principle for completely novel forms of quantum correlations. In particular, quantum nonlocality can be demonstrated here without the need of having various input settings, but only by considering the joint…

The future progress of semi-device independent quantum information science depends crucially on our ability to bound the strength of the nonlocal correlations achievable with finite dimensional quantum resources. In this work, we…

Quantum Physics · Physics 2014-02-05 Miguel Navascues , Gonzalo de la Torre , Tamas Vertesi

We develop a protocol for entanglement generation in the quantum internet that allows a repeater node to use $n$-qubit Greenberger-Horne-Zeilinger (GHZ) projective measurements that can fuse $n$ successfully-entangled {\em links}, i.e.,…

Quantum Physics · Physics 2022-05-17 Ashlesha Patil , Mihir Pant , Dirk Englund , Don Towsley , Saikat Guha