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Related papers: Epsilon-measures of entanglement

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We propose a measurement-based method to produce a maximally-entangled state from a partially-entangled pure state. Our goal can be thought of as entanglement distillation from a single copy of a partially-entangled state. The present…

Quantum Physics · Physics 2012-10-17 Yukihiro Ota , Sahel Ashhab , Franco Nori

Here we propose an experimental set-up in which it is possible to measure the entanglement of a two-mode Gaussian state, be it pure or mixed, using only simple linear optical devices. After a proper unitary manipulation of the two-mode…

Quantum Physics · Physics 2015-06-26 Gustavo Rigolin , Marcos C. de Oliveira

Entanglement is the key feature of many-body quantum systems, and the development of new tools to probe it in the laboratory is an outstanding challenge. Measuring the entropy of different partitions of a quantum system provides a way to…

We discuss the monotonicity under local operations and classical communication (LOCC) of systematically constructed quantities aiming at quantification of entanglement properties of multipartite quantum systems. The so-called generalized…

Quantum Physics · Physics 2009-11-13 Rafal Demkowicz-Dobrzanski , Andreas Buchleitner , Marek Kus , Florian Mintert

Quantum entanglement between several particles is essential for applications like quantum metrology or quantum cryptography, but it is also central for foundational phenomena like quantum non-locality. This leads to the problem of…

Quantum Physics · Physics 2025-10-10 Lisa T. Weinbrenner , Otfried Gühne

The expected indefinite causal structure in quantum gravity poses a challenge to the notion of entanglement: If two parties are in an indefinite causal relation of being spacelike and timelike, can they still be entangled? If so, how does…

Quantum Physics · Physics 2018-02-27 Ding Jia

Measures of entanglement can be employed for the analysis of numerous quantum information protocols. Due to computational convenience, logarithmic negativity is often the choice in the case of continuous variable systems. In this work, we…

A new family of positive, trace-preserving maps is introduced. It is defined using the mutually unbiased measurements, which generalize the notion of mutual unbiasedness of orthonormal bases. This family allows one to define entanglement…

Quantum Physics · Physics 2021-11-30 Katarzyna Siudzińska , Dariusz Chruściński

In this paper, we generalize the residual entanglement to the case of multipartite states in arbitrary dimensions by making use of a new method. Through the introduction of a special entanglement measure, the residual entanglement of mixed…

Quantum Physics · Physics 2007-05-23 Chang-shui Yu , He-shan Song

A general framework is developed for separating classical and quantum correlations in a multipartite system. Entanglement is defined as the difference in the correlation information encoded by the state of a system and a suitably defined…

Quantum Physics · Physics 2007-05-23 M. Hossein Partovi

We recently showed that multipartite correlations between outcomes of random observables detect quantum entanglement in all pure and some mixed states. In this followup article we further develop this approach, derive a maximal amount of…

Quantum Physics · Physics 2016-10-11 Minh Cong Tran , Borivoje Dakic , Wieslaw Laskowski , Tomasz Paterek

We investigate the properties and relations of two classes of operational bipartite and multipartite entanglement measures, the so-called source and the accessible entanglement. The former measures how easy it is to generate a given state…

Quantum Physics · Physics 2017-01-31 Katharina Schwaiger , Barbara Kraus

Previously proposed measures of entanglement, such as entanglement of formation and assistance, are shown to be special cases of the relative entropy of entanglement. The difference between these measures for an ensemble of mixed states is…

Quantum Physics · Physics 2009-10-31 L. Henderson , V. Vedral

We show how to estimate a broad class of multipartite entanglement measures from Bell basis measurement data. In addition to lowering the experimental requirements relative to previously known methods of estimating these measures, our…

Quantum Physics · Physics 2023-07-12 Jacob L. Beckey , G. Pelegrí , Steph Foulds , Natalie J. Pearson

Although quantum entanglement has already been verified experimentally and applied in quantum computing, quantum sensing and quantum networks, most of the existing measures cannot characterize the entanglement faithfully. In this work, by…

Quantum Physics · Physics 2023-01-10 Zhi-Xiang Jin , Shao-Ming Fei , Xianqing Li-Jost , Cong-Feng Qiao

We propose a measure of entanglement that can be computed for any pure state of an $M$-qubit system. The entanglement measure has the form of a distance that we derive from an adapted application of the Fubini-Study metric. This measure is…

In this work, we perform a series of phonon counting measurement with different methods in a 3-mode optomechanical system, and we compare the difference of the entanglement after measurement. In this article we focus on the two cases:…

Quantum Physics · Physics 2017-10-03 Zhe Li

So-called direct measurements of entanglement are collective measurements on multiple copies of a (bipartite or multipartite) quantum system that directly provide one a value for some entanglement measure, such as the concurrence for…

Quantum Physics · Physics 2009-08-03 S. J. van Enk

We consider the problem of detecting the dimensionality of entanglement with the use of correlations between measurements in randomized directions. First, exploiting the recently derived covariance matrix criterion for the entanglement…

Quantum Physics · Physics 2023-07-20 Shuheng Liu , Qiongyi He , Marcus Huber , Otfried Gühne , Giuseppe Vitagliano

Entanglement of formation quantifies the entanglement of a state in terms of the entropy of entanglement of the least entangled pure state needed to prepare it. An analytical expression for this measure exists only for special cases, and…

Quantum Physics · Physics 2019-05-29 Spyros Tserkis , Sho Onoe , Timothy C. Ralph