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Related papers: Testing Scalable Bell Inequalities for Quantum Gra…

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Bell inequalities were meant to test quantum mechanics vs local hidden variable models, but can also be used to verify entanglement. For entanglement verification purposes one assumes the validity of quantum mechanics as well as quantum…

Quantum Physics · Physics 2015-05-13 Pavel Lougovski , S. J. van Enk

We introduce a set of Bell inequalities for a three-qubit system. Each inequality within this set is violated by all generalized GHZ states. More entangled a generalized GHZ state is, more will be the violation. This establishes a relation…

Quantum Physics · Physics 2017-11-02 Arpan Das , Chandan Datta , Pankaj Agrawal

Measurements in quantum theory can fail to be jointly measurable. Like entanglement, this incompatibility of measurements is necessary but not sufficient for violating Bell inequalities. The (in)compatibility relations among a set of…

Quantum Physics · Physics 2024-11-21 Shiv Akshar Yadavalli , Nikola Andrejic , Ravi Kunjwal

We consider quantum systems composed of $N$ qubits, and the family of all Bell's correlation inequalities for two two-valued measurements per site. We show that if a $N$-qubit state $\rho$ violates any of these inequalities, then it is at…

Quantum Physics · Physics 2009-11-07 A. Acin , V. Scarani , M. M. Wolf

We examine the use of noiseless subsystems for quantum information processing between two parties who do not share a common reference frame. In particular we focus on Bell inequalities in curved spaces and outline a theoretical procedure to…

Quantum Physics · Physics 2007-05-23 Jonathan L. Ball

In practical quantum networks, a variety of multi-qubit stabilized states emitted from independent sources are distributed among the agents, and the correlations across the entire network can be derived from each agent's local measurements…

Quantum Physics · Physics 2021-05-28 Li-Yi Hsu , Ching-Hsu Chen

Quantum self-testing is the task of certifying quantum states and measurements using the output statistics solely, with minimal assumptions about the underlying quantum system. It is based on the observation that some extremal points in the…

Quantum Physics · Physics 2023-09-07 Kishor Bharti , Maharshi Ray , Zhen-Peng Xu , Masahito Hayashi , Leong-Chuan Kwek , Adán Cabello

Detection and quantification of entanglement in quantum resources are two key steps in the implementation of various quantum-information processing tasks. Here, we show that Bell-type inequalities are not only useful in verifying the…

Quantum Physics · Physics 2011-02-28 Yeong-Cherng Liang , Tamas Vertesi , Nicolas Brunner

The self-testing protocols refer to novel device-independent certification schemes wherein the devices are uncharacterised, and the dimension of the system remains unspecified. The optimal quantum violation of a Bell's inequality…

Quantum Physics · Physics 2024-08-21 Rajdeep Paul , Souradeep Sasmal , A. K. Pan

Semi-device-independent certification of an unsharp instrument has recently been demonstrated [New J. Phys. 21, 083034 (2019)] based on the sequential sharing of quantum advantages in a prepare-measure communication game by assuming the…

Quantum Physics · Physics 2023-11-09 Prabuddha Roy , A. K. Pan

Quantum network coding has been proposed to improve resource utilization to support distributed computation but has not yet been put in to practice. We investigate a particular implementation of quantum network coding using…

In the near-term "NISQ"-era of noisy, intermediate-scale, quantum hardware and beyond, reliably determining the quality of quantum devices becomes increasingly important: users need to be able to compare them with one another, and make an…

Quantum Physics · Physics 2021-04-23 Arjan Cornelissen , Johannes Bausch , András Gilyén

We present a Bell-type inequality for four-qubit systems. Using the inequality we investigate quantum nonlocality of a generic family of states $\left|G_{abcd}\right >$ [Phys. Rev. A 65, 052112 (2002)] and several canonical four-qubit…

Quantum Physics · Physics 2017-06-07 Dong Ding , Fengli Yan , Ting Gao

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

Quantum information science has profoundly changed the ways we understand, store, and process information. A major challenge in this field is to look for an efficient means for classifying quantum state. For instance, one may want to…

Quantum Physics · Physics 2017-05-03 Yue-Chi Ma , Man-Hong Yung

The characterization of the set of quantum correlations is a problem of fundamental importance in quantum information. The question whether every proper (tight) Bell inequality is violated in Quantum theory is an intriguing one in this…

Quantum Physics · Physics 2021-08-04 Ravishankar Ramanathan

Bell nonlocality is a fundamental phenomenon of quantum physics as well as an essential resource for various tasks in quantum information processing. It is known that for the observation of nonlocality the measurements on a quantum system…

Quantum Physics · Physics 2025-07-16 Martin Plávala , Otfried Gühne , Marco Túlio Quintino

The difference between ideal experiments to test Bell's weak nonlocality and the real experiments leads to loopholes. Ideal experiments involve either inequalities (Bell) or equalities (Greenberger, Horne, Zeilinger). Every real experiment…

Quantum Physics · Physics 2009-11-06 Roberto M. Basoalto , Ian C. Percival

As quantum computing technology slowly matures and the number of available qubits on a QPU gradually increases, interest in assessing the capabilities of quantum computing hardware in a scalable manner is growing. One of the key properties…

Quantum Physics · Physics 2024-02-02 René Zander , Colin Kai-Uwe Becker

Bell inequalities reveal the fundamentally nonlocal character of quantum mechanics. In this regard, one of the interesting problems is to explore all possible Bell inequalities that demonstrate a gap between local and nonlocal quantum…

Quantum Physics · Physics 2026-02-10 Palash Pandya , Shubhayan Sarkar , Remigiusz Augusiak