English
Related papers

Related papers: Additional information decreases the estimated ent…

200 papers

We develop a novel necessary condition of quantum correlation. It is utilized to construct $d$-level bipartite Bell-type inequality which is strongly resistant to noise and requires only analyses of $O(d)$ measurement outcomes compared to…

Quantum Physics · Physics 2007-09-14 Che-Ming Li , Li-Yi Hsu , Yueh-Nan Chen , Der-San Chuu , Tobias Brandes

Entanglement is the fundamental quantum property behind the now popular field of quantum transport of information. This quantum property is incompatible with the separation of a single system into two uncorrelated subsystems. Consequently,…

Statistical Mechanics · Physics 2009-11-07 Filippo Giraldi , Paolo Grigolini

Nonlocality, evidenced by the violation of Bell inequalities, not only signifies entanglement but also highlights measurement incompatibility in quantum systems. Utilizing the generalized Clauser-Horne-Shimony-Holt (CHSH) Bell inequality,…

We study the CHSH inequality for a system of two spin $j$ particles, for generic $j$. The CHSH operator is constructed using a set of unitary, Hermitian operators $\left\{ A_{1},A_{2},B_{1},B_{2}\right\} $. The expectation value of the CHSH…

Quantum Physics · Physics 2023-05-03 Giovani Peruzzo , Silvio Paolo Sorella

In quantum information theory, the reliable and effective detection of entanglement is of paramount importance. However, given an unknown state, assessing its entanglement is a challenging task. To attack this problem, we investigate the…

Quantum Physics · Physics 2015-12-09 Jochen Szangolies , Hermann Kampermann , Dagmar Bruß

Bell's theorem states that, to simulate the correlations created by measurement on pure entangled quantum states, shared randomness is not enough: some "non-local" resources are required. It has been demonstrated recently that all…

Quantum Physics · Physics 2009-11-10 Nicolas Brunner , Nicolas Gisin , Valerio Scarani

The entanglement of assistance quantifies the amount of entanglement that can be concentrated among a group of spatially-separated parties using the assistance of some auxiliary system. In this paper we study the entanglement of assistance…

Quantum Physics · Physics 2023-10-11 Klée Pollock , Ge Wang , Eric Chitambar

According to Bell's theorem a large class of hidden-variable models obeying Bell's notion of local causality conflict with the predictions of quantum mechanics. Recently, a Bell-type theorem has been proven using a weaker notion of local…

Quantum Physics · Physics 2012-03-05 Samuel Portmann , Adrian Wuethrich

It is well-known that in certain scenarios weakly entangled states can generate stronger nonlocal effects than their maximally entangled counterparts. In this paper, we consider violations of the CHSH Inequality when one party has…

Quantum Physics · Physics 2018-06-13 Daniel Dilley , Eric Chitambar

Bell's test, initially devised to distinguish quantum theory from local hidden variable models through {violations of local bounds}, is also a common tool for detecting entanglement. For this purpose, one can assume the quantum description…

Quantum Physics · Physics 2026-04-21 Liang-Liang Sun , Yong-Shun Song , Sixia Yu

Entanglement is one of the most fascinating concepts of modern physics. In striking contrast to its abstract, mathematical foundation, its practical side is, however, remarkably underdeveloped. Even for systems of just two orbitals or sites…

Quantum Physics · Physics 2022-07-08 Lexin Ding , Zoltan Zimboras , Christian Schilling

We consider a range of "theories" that violate the uncertainty relation for anti-commuting observables derived in [JMP, 49, 062105 (2008)]. We first show that Tsirelson's bound for the CHSH inequality can be derived from this uncertainty…

Quantum Physics · Physics 2011-05-02 Greg Ver Steeg , Stephanie Wehner

Squashed entanglement is a measure for the entanglement of bipartite quantum states. In this paper we present a lower bound for squashed entanglement in terms of a distance to the set of separable states. This implies that squashed…

Quantum Physics · Physics 2012-07-23 Fernando G. S. L. Brandao , Matthias Christandl , Jon Yard

Quantum entanglement is usually revealed via a well aligned, carefully chosen set of measurements. Yet, under a number of experimental conditions, for example in communication within multiparty quantum networks, noise along the channels or…

A sufficient condition for entanglement in two-mode continuous systems is constructed based on interference visibility and the uncertainty of the total particle number. The observables to be measured (particle numbers and particle number…

Quantum Physics · Physics 2007-05-23 Geza Toth , Christoph Simon , Juan Ignacio Cirac

Some thermodynamical properties of solids, such as heat capacity and magnetic susceptibility, have recently been shown to be linked to the amount of entanglement in a solid. However this entanglement may appear a mere mathematical artifact…

Quantum Physics · Physics 2016-09-08 G. De Chiara , C. Brukner , R. Fazio , G. M. Palma , V. Vedral

Using the concept of non-degenerate Bell inequality, we show that quantum entanglement, the critical resource for various quantum information processing tasks, can be quantified for any unknown quantum states in a semi-device-independent…

Quantum network protocols depend on the availability of shared entanglement. Given that entanglement generation and distribution are affected by noise, characterization of the shared entangled states is essential to bound the errors of the…

Quantum Physics · Physics 2025-10-31 Noah Kaufmann , Maria Quadeer , David Elkouss

When an entangled state is transformed into another one with probability one by local operations and classical communication, the quantity of entanglement decreases. This letter shows that entanglement lost in the manipulation can be…

Quantum Physics · Physics 2009-10-31 Fumiaki Morikoshi

We introduce an entanglement-depth criterion optimized for planar quantum squeezed (PQS) states. It is connected with the sensitivity of such states for estimating an arbitrary, not necessarily small phase. We compare numerically our…