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Related papers: All Entangled Quantum States Are Nonlocal

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We find that a bipartite quantum state is entangled if and only if it is quantum coherent with respect to complete bases of states in the corresponding system that are distinguishable under local quantum operations and classical…

Quantum Physics · Physics 2022-01-19 Asmitha Mekala , Ujjwal Sen

A key problem in quantum information science is to determine optimal protocols for the interconversion of entangled states shared between remote parties. While for two parties a large number of results in this direction is available, the…

Quantum Physics · Physics 2025-05-26 Alexander Streltsov

Entanglement is one of the key feature of quantum world and any entanglement measure must satisfy some basic laws. Most important of them is the invariance of entanglement under local unitary operations. We show that this is no longer true…

Quantum Physics · Physics 2014-04-25 Arun Kumar Pati

Nonlocality exhibited by ensembles of composite quantum states, wherein local operations and classical communication (LOCC) yield suboptimal discrimination probabilities compared to global strategies, is one of the striking nonclassical…

Quantum Physics · Physics 2025-12-02 Samrat Sen

We consider a quantum system subject to superselection rules, for which certain restrictions apply to the quantum operations that can be implemented. It is shown how the notion of quantum-nonlocality has to be redefined in the presence of…

Quantum Physics · Physics 2009-11-10 F. Verstraete , J. I. Cirac

A bipartite state which is secretly chosen from a finite set of known entangled pure states cannot be immediately useful in standard quantum information processing tasks. To effectively make use of the entanglement contained in this unknown…

Quantum Physics · Physics 2015-05-14 Yangjia Li , Runyao Duan , Mingsheng Ying

Understanding the relation between the different forms of inseparability in quantum mechanics is a longstanding problem in the foundations of quantum theory and has implications for quantum information processing. Here we make progress in…

Quantum Physics · Physics 2013-04-09 Daniel Cavalcanti , Antonio Acin , Nicolas Brunner , Tamas Vertesi

We show that any Bell local state, with a hidden nonlocality that can be revealed by local filtering, is more, or equally, entangled than nonlocal states. More precisely, it can be deterministically transformed into a nonlocal state, by…

Quantum Physics · Physics 2017-12-06 S. Camalet

A standard approach to quantifying resources is to determine which operations on the resources are freely available, and to deduce the partial order over resources that is induced by the relation of convertibility under the free operations.…

A set of all states of a bi-partite quantum system can be divided into subsets each of which contains states with the same degree of entanglement. In this paper we address a question whether local operations (without classical…

Quantum Physics · Physics 2007-07-31 Mario Ziman , Vladimir Buzek

We experimentally demonstrate, with an all-optical setup, a nonlocal deterministic quantum non-demolition interaction gate applicable to quantum states at nodes separated by a physical distance and connected by classical communication…

Quantum Physics · Physics 2016-11-25 Shota Yokoyama , Ryuji Ukai , Jun-ichi Yoshikawa , Petr Marek , Radim Filip , Akira Furusawa

In quantum systems, entanglement corresponds to nonclassical correlation of nonlocal observables. Thus, entanglement (or, to the contrary, separability) of a given quantum state is not uniquely determined by properties of the state, but may…

Quantum Physics · Physics 2012-05-21 Iacopo Pozzana

Recently, Halder \emph{et al.} [S. Halder \emph{et al.}, Phys. Rev. Lett. \textbf{122}, 040403 (2019)] present two sets of strong nonlocality of orthogonal product states based on the local irreducibility. However, for a set of locally…

Quantum Physics · Physics 2020-07-27 Zhi-Chao Zhang , Guojing Tian , Tian-Qing Cao

Quantum entanglement is known to provide a strong advantage in many two-party distributed tasks. We investigate the question of how much entanglement is needed to reach optimal performance. For the first time we show that there exists a…

Quantum Physics · Physics 2015-08-25 Laura Mančinska , Thomas Vidick

We investigate the problem of "nonlocal" computation, in which separated parties must compute a function with nonlocally encoded inputs and output, such that each party individually learns nothing, yet together they compute the correct…

Quantum Physics · Physics 2017-08-01 Noah Linden , Sandu Popescu , Anthony J. Short , Andreas Winter

Quantum nonlocality is an inherently non-classical feature of quantum mechanics and manifests itself through violation of Bell inequalities for nonlocal games. We show that in a fairly general setting, a simple extension of a nonlocal game…

Quantum Physics · Physics 2017-06-09 Carl A. Miller , Yaoyun Shi

We consider generic pure $n$-qubit states and a general class of pure states of arbitrary dimensions and arbitrarily many subsystems. We characterize those states which can be reached from some other state via Local Operations assisted by…

Quantum Physics · Physics 2017-02-01 C. Spee , J. I. de Vicente , D. Sauerwein , B. Kraus

Understanding the role that quantum entanglement plays as a resource in various information processing tasks is one of the crucial goals of quantum information theory. Here we propose a new perspective for studying quantum entanglement:…

Quantum Physics · Physics 2015-09-23 L. Czekaj , M. Pawlowski , T. Vertesi , A. Grudka , M. Horodecki , R. Horodecki

Measurements on entangled quantum states can produce outcomes that are nonlocally correlated. But according to Tsirelson's theorem, there is a quantitative limit on quantum nonlocality. It is interesting to explore what would happen if…

Quantum Physics · Physics 2010-04-14 Anthony J. Short , Jonathan Barrett

While all bipartite pure entangled states violate some Bell inequality, the relationship between entanglement and non-locality for mixed quantum states is not well understood. We introduce a simple and efficient algorithmic approach for the…

Quantum Physics · Physics 2009-11-07 Barbara M. Terhal , Andrew C. Doherty , David Schwab