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Related papers: Quantum networks self-test all entangled states

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Entangled quantum states are essential ingredients for many quantum technologies, but they must be validated before they are used. As a full characterization is prohibitively resource-intensive, recent work has focused on developing methods…

Entanglement allows for the nonlocality of quantum theory, which is the resource behind device-independent quantum information protocols. However, not all entangled quantum states display nonlocality, and a central question is to determine…

Quantum Physics · Physics 2016-11-09 Daniel Cavalcanti , Leonardo Guerini , Rafael Rabelo , Paul Skrzypczyk

The verification of quantum devices is an important aspect of quantum information, especially with the emergence of more advanced experimental implementations of computation and secure communication. Within this, the theory of…

Quantum Physics · Physics 2016-07-08 Ivan Šupić , Matty J. Hoban

The task of classifying the entanglement properties of a multipartite quantum state poses a remarkable challenge due to the exponentially increasing number of ways in which quantum systems can share quantum correlations. Tackling such…

Quantum Physics · Physics 2020-06-24 Cillian Harney , Stefano Pirandola , Alessandro Ferraro , Mauro Paternostro

Self-testing refers to the fact that, in some quantum devices, both states and measurements can be assessed in a black-box scenario, on the sole basis of the observed statistics, i.e. without reference to any prior device calibration. Only…

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.…

The standard definition of genuine multipartite entanglement stems from the need to assess the quantum control over an ever-growing number of quantum systems. We argue that this notion is easy to hack: in fact, a source capable of…

Quantum Physics · Physics 2020-12-21 Miguel Navascues , Elie Wolfe , Denis Rosset , Alejandro Pozas-Kerstjens

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

Quantum steering is an asymmetric form of quantum nonlocality where one can detect whether a measurement on one system can steer or change another distant system. It is well-known that there are quantum states that are entangled but…

Quantum Physics · Physics 2026-04-03 Shubhayan Sarkar

Self-testing protocols are methods to determine the presence of shared entangled states in a device independent scenario, where no assumptions on the measurements involved in the protocol are made. A particular type of self-testing…

Quantum Physics · Physics 2021-03-24 Ivan Šupić , Daniel Cavalcanti , Joseph Bowles

Self-testing allows us to determine, through classical interaction only, whether some players in a non-local game share particular quantum states. Most work on self-testing has concentrated on developing tests for small states like one pair…

Quantum Physics · Physics 2016-05-04 Matthew McKague

Bipartite and multipartite entangled states are basic ingredients for constructing quantum networks and their accurate verification is crucial to the functioning of the networks, especially for untrusted networks. Here we propose a simple…

Quantum Physics · Physics 2021-12-28 Yun-Guang Han , Zihao Li , Yukun Wang , Huangjun Zhu

This short note describes a method to tackle the (bipartite) quantum separability problem. The method can be used for solving the separability problem in an experimental setting as well as in the purely mathematical setting. The idea is to…

Quantum Physics · Physics 2007-05-23 L. M. Ioannou , B. C. Travaglione

Continuous-variable quantum states are of particular importance in various quantum information processing tasks including quantum communication and quantum sensing. However, a bottleneck has emerged with the fast increasing in size of the…

Quantum Physics · Physics 2021-10-13 Ye-Chao Liu , Jiangwei Shang , Xiangdong Zhang

Quantum networks with bipartite resources and shared randomness present the simplest infrastructure for implementing a future quantum internet. Here, we shall investigate which kinds of entanglement can or cannot be generated from this kind…

Quantum Physics · Physics 2025-03-13 Xiang Zhou , Zhen-Peng Xu , Liang-Liang Sun , Chunfeng Wu , Sixia Yu

As quantum technologies advance, the ability to generate increasingly large quantum states has experienced rapid development. In this context, the verification and estimation of large entangled systems represents one of the main challenges…

Quantum Physics · Physics 2022-03-30 Joshua Morris , Valeria Saggio , Aleksandra Gočanin , Borivoje Dakić

Quantum self-testing addresses the following question: is it possible to verify the existence of a multipartite state even when one's measurement devices are completely untrusted? This problem has seen abundant activity in the last few…

Quantum Physics · Physics 2019-01-30 Spencer Breiner , Amir Kalev , Carl A. Miller

The certification of randomness is essential for both fundamental science and information technologies. Unlike traditional random number generators, randomness obtained from nonlocal correlations is fundamentally guaranteed to be…

Previous theoretical works showed that all pure two-qubit entangled states can generate one bit of local randomness and can be self-tested through the violation of proper Bell inequalities. We report an experiment in which nearly pure…

Quantum Physics · Physics 2019-03-14 S. Gómez , A. Mattar , I. Machuca , E. S. Gómez , D. Cavalcanti , O. Jiménez Farías , A. Acín , G. Lima

Entangled physical systems are an important resource in quantum information. Some authors claim that in fact all quantum states are entangled. In this paper we show that this claim is incorrect and we discuss in operational way differences…

Quantum Physics · Physics 2016-10-07 Marian Kupczynski