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Related papers: Robust self-testing of two-qubit states

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Self-testing protocols enable the certification of quantum systems in a device-independent manner, i.e. without knowledge of the inner workings of the quantum devices under test. Here, we demonstrate this high standard for characterization…

Self-testing refers to a device-independent way to uniquely identify the state and the measurement for uncharacterized quantum devices. The only information required comprises the number of measurements, the number of outputs of each…

Quantum Physics · Physics 2019-07-16 Xinhui Li , Yukun Wang , Yunguang Han , Fei Gao , Qiaoyan Wen

Bell-inequality violations establish that two systems share some quantum entanglement. We give a simple test to certify that two systems share an asymptotically large amount of entanglement, n EPR states. The test is efficient: unlike…

Quantum Physics · Physics 2018-09-06 Rui Chao , Ben W. Reichardt , Chris Sutherland , Thomas Vidick

Self-testing is a method to characterise an arbitrary quantum system based only on its classical input-output correlations, and plays an important role in device-independent quantum information processing as well as quantum complexity…

Quantum Physics · Physics 2022-05-18 Tony Metger , Thomas Vidick

Self-testing is a promising approach to certifying quantum states or measurements. Originally, it relied solely on the outcome statistics of the measurements involved in a device-independent (DI) setup. Extra physical assumptions about the…

Quantum Physics · Physics 2024-06-14 Gábor Drótos , Károly F. Pál , Abdelmalek Taoutioui , Tamás Vértesi

Nonlocality and entanglement are not only the fundamental characteristics of quantum mechanics but also important resources for quantum information and computation applications. Exploiting the quantitative relationship between the two…

Quantum Physics · Physics 2020-04-20 Zhaofeng Su , Haisheng Tan , Xiangyang Li

Recently, the fast development of quantum technologies led to the need for tools allowing the characterization of quantum resources. In particular, the ability to estimate non-classical aspects, e.g. entanglement and quantum discord, in…

Self-testing--the attractive possibility to infer the underlying physics of a quantum device in a black-box scenario--has gained increased traction in recent years, with applications to device-independent quantum information processing.…

Quantum Physics · Physics 2026-03-12 Moisés Bermejo Morán , Ravishankar Ramanathan

Certification of quantum systems and their properties has become a field of intensive studies. Here, taking advantage of the one-sided device-independent scenario (known also as quantum steering scenario), we propose a self-testing scheme…

We investigate the decay of entanglement, due to decoherence, of multi-qubit systems that are initially prepared in highly (in some cases maximally) entangled states. We assume that during the decoherence processes each qubit of the system…

Quantum Physics · Physics 2009-11-13 A. Borras , A. P. Majtey , A. R. Plastino , M. Casas , A. Plastino

Robust, accurate and efficient quantum tomography is key for future quantum technologies. Traditional methods are impractical for even medium sized systems and are not robust against noise and errors. Here we report on an experimental…

Quantum Physics · Physics 2016-07-27 Robert J. Chapman , Christopher Ferrie , Alberto Peruzzo

We describe and realize an experimental procedure for assessing the incompatibility of two qubit measurements. The experiment consists in a state discrimination task where either measurement is used according to some partial intermediate…

Recently, Fan \textit{et al.} [Mod. Phys. Lett. A 36, 2150223 (2021)], presented a generalized Clauser-Horne-Shimony-Holt (CHSH) inequality, to identify $N$-qubit Greenberger-Horne-Zeilinger (GHZ) states. They showed an interesting…

Quantum Physics · Physics 2022-06-09 Gang-Gang He , Xing-Yan Fan , Fu-Lin Zhang

We investigate the behavior of the maximal violations of the CHSH inequality and V$\grave{e}$rtesi's inequality under the local filtering operations. An analytical method has been presented for general two-qubit systems to compute the…

Quantum Physics · Physics 2017-04-27 Ming Li , Huihui Qin , Jing Wang , Shao-Ming Fei , Chang-Pu Sun

A central task in quantum information science is state certification: testing whether an unknown state is $\epsilon_1$-close to a fixed target state, or $\epsilon_2$-far. Recent work has shown that surprisingly simple measurement…

Quantum Physics · Physics 2026-02-13 Andrea Coladangelo , Jerry Li , Joseph Slote , Ellen Wu

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

Self-testing is a procedure for characterizing quantum resources with the minimal level of trust. Up to now it has been used as a device-independent certification tool for particular quantum measurements, channels, and pure entangled…

Quantum Physics · Physics 2021-01-01 Flavio Baccari , Remigiusz Augusiak , Ivan Šupić , Antonio Acín

The violation of a Bell inequality implies the existence of nonlocality, making device-independent randomness certification possible. This paper derives a tight upper bound for the maximal quantum violation of Gisin's elegant Bell…

Quantum Physics · Physics 2025-02-14 Dan-Dan Hu , Meng-Yan Li , Fen-Zhuo Guo , Yu-Kun Wang , Hai-Feng Dong , Fei Gao

The theorem developed by John Bell constituted the starting point of a revolution that translated a philosophical question about the nature of reality into the broad and intense field of research of the quantum information technologies. We…

Quantum Physics · Physics 2023-10-16 Antonio Mandarino , Giovanni Scala

We study the robustness of the GHZ (or ``cat'') class of multi-partite states under decoherence. The noise model is described by a general completely positive map for qubits independently coupled to the environment. In particular, the…

Quantum Physics · Physics 2007-05-23 Somshubhro Bandyopadhyay , Daniel A. Lidar