English
Related papers

Related papers: Necessary and sufficient detection efficiency for …

200 papers

Violation of Mermin's and Svetlichny's inequalities can rule out the predictions of local hidden variable theory and can confirm the existence of true nonlocal correlation for n-particle pure quantum systems. Here we demonstrate the…

Quantum Physics · Physics 2019-05-28 Manoranjan Swain , Amit Rai , Bikash K. Behera , Prasanta K. Panigrahi

We derive a set of Bell-type inequalities for arbitrarily high-dimensional systems, based on the assumption of partial separability in the hybrid local-nonlocal hidden variable model. Partially entangled states would not violate the…

Quantum Physics · Physics 2015-05-20 Jing-Ling Chen , Dong-Ling Deng , Hong-Yi Su , Chunfeng Wu , C. H. Oh

Bell's theorem teaches us that there are quantum correlations that can not be simulated by just shared randomness (Local Hidden variable). There are some recent results which simulate singlet correlation by using either 1 cbit or a binary…

Quantum Physics · Physics 2013-11-18 Manik Banik , MD Rajjak Gazi , Subhadipa Das , Ashutosh Rai , Samir Kunkri

We derive a Bell inequality based on a generalized quasiprobability function which is parameterized by one non-positive real value. Two types of known Bell inequalities formulated in terms of the Wigner and Q functions are included as…

Quantum Physics · Physics 2009-08-06 Seung-Woo Lee , Hyunseok Jeong , Dieter Jaksch

We show that hybrid local measurements combining homodyne measurements and photodetection provide violations of a Bell inequality with arbitrarily low photodetection efficiency. This is shown in two different scenarios: when one part…

Loophole-free Bell tests are essential if one wishes to perform device-independent quantum key distribution (QKD), since any loophole could be used by a potential adversary to undermine the security of the protocol. Crucial work by Eberhard…

In this note we wish to demonstrate that the concept of efficiency loophole, as far as a local realistic model is concerned, is a self-defeating one since it implies that the static fields (for example, electric or gravitational) of and…

General Physics · Physics 2007-05-23 M. R. Mahdavi

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

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable $n$-particle density operators on an arbitrary dimensional space. This methodology enables us to truly derive a tight quadratic inequality as tests for…

Quantum Physics · Physics 2009-11-07 Koji Nagata , Masato Koashi , Nobuyuki Imoto

In this paper we study the nonlocal properties of two-qubit Werner states parameterized by the visibility parameter 0<p<1. New family of Bell inequalities are constructed which prove the two-qubit Werner states to be nonlocal for the…

Quantum Physics · Physics 2009-11-13 T. Vértesi

The certification of quantum nonlocality, which has immense significance in architecting device-independent technologies, confronts severe experimental challenges. Detection loophole, originating from the unavailability of perfect…

Quantum Physics · Physics 2024-05-21 Subhendu B. Ghosh , Snehasish Roy Chowdhury , Ranendu Adhikary , Arup Roy , Tamal Guha

We provide a detailed analysis of the recently proposed setup for a loophole-free test of Bell inequality using conditionally generated non-Gaussian states of light and balanced homodyning. In the proposed scheme, a two-mode squeezed vacuum…

Quantum Physics · Physics 2009-11-10 R. Garcia-Patron , J. Fiurasek , N. J. Cerf

We introduce for a general correlation scenario a new simulation model, a local quasi hidden variable (LqHV) model, where locality and the measure-theoretic structure inherent to an LHV model are preserved but positivity of a simulation…

Quantum Physics · Physics 2012-02-21 Elena R. Loubenets

Bell inequalities provide a fundamental tool for probing nonlocal correlations, yet their quantum bound, that is, the maximal value attainable through quantum strategies, is rarely accessible analytically. In this work, we introduce a…

Quantum Physics · Physics 2025-11-25 Patryk Michalski , Arturo Konderak , Wojciech Bruzda , Remigiusz Augusiak

Bell-type inequalities allow for experimental testing of local hidden variable theories. In the present work we show the violation of Mermin's inequalities in IBM's five-qubit quantum computers, ruling out the local realism hypothesis in…

Quantum Physics · Physics 2024-01-19 Diego González , Diego Fernández de la Pradilla , Guillermo González

The establishment of nonlocal correlations, obtained through the violation of a Bell inequality, is not only important from a fundamental point of view, but constitutes the basis for device-independent quantum information technologies.…

An efficiency-loophole-free quantum key distribution (QKD) scheme is proposed, which involves no hardware change but a modification in the data post-processing step. The scheme applies to a generic class of detection systems which allow…

Quantum Physics · Physics 2008-12-24 Xiongfeng Ma , Tobias Moroder , Norbert Lütkenhaus

The observation that violating Bell inequalities with high probability is possible even when the local measurements are randomly chosen, as occurs when local measurements cannot be suitably calibrated or the parties do not share a common…

Quantum Physics · Physics 2013-08-06 Esteban S. Gómez , Gustavo Cañas , Johanna F. Barra , Adán Cabello , Gustavo Lima

We study the nonlocal properties of two-qubit maximally-entangled and N-qubit Greenberger-Horne-Zeilinger states under local decoherence. We show that the (non)resilience of entanglement under local depolarization or dephasing is not…

Quantum Physics · Physics 2015-06-04 Rafael Chaves , Daniel Cavalcanti , Leandro Aolita , Antonio Acín

In device-independent quantum information processing Bell inequalities are not only used as detectors of nonlocality, but also as certificates of relevant quantum properties. In order for these certificates to work, one very often needs…

Quantum Physics · Physics 2019-11-06 Remigiusz Augusiak , Alexia Salavrakos , Jordi Tura , Antonio Acín