Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Mathematical Physics

On states of perfect correlation

Siendong Huang

Published Nov 1, 2008• 8 citations
Publisher

Abstract

For finite-dimensional systems, states satisfying perfect correlation are just maximally entangled states that play an essential role in quantum information theory. Thus perfect correlation may be a key to entanglement phenomena. For general systems, Einstein–Podolsky–Rosen type states are characterized by perfect correlation and their properties are discussed. Conditions equivalent to perfect correlation are found. As an application of perfect correlation, all Einstein–Podolsky–Rosen type states on a two-particle system are given. Unlike in finite-dimensional systems, they are generally not quasiequivalent.

DOI
10.1063/1.3012383

Related papers

The Einstein-Podolsky-Rosen Paradox and Entanglement 1: Signatures of EPR correlations for continuous variables

M. D. Reid

A generalization of the 1935 Einstein-Podolsky-Rosen (EPR) argument for measurements with continuous variable outcomes is presented to establish criteria for the demonstration of the EPR paradox, for situations where the correlation between spatially separated subsystems is not perfect. Two types of criteria for EPR correlations are determined. The first type are based on measurements of the variances of conditional probability distributions and are necessary to reflect directly the situation of the original EPR paradox. The second weaker set of EPR criteria are based on the proven failure of (Bell-type) local realistic theories which could be consistent with a local quantum description for each subsystem. The relationship with criteria sufficient to prove entanglement is established, to show that any demonstration of EPR correlations will also signify entanglement. It is also shown how a demonstration of entanglement between two spatially separated subsystems, if not able to interpreted as a violation of a Bell-type inequality, may be interpreted as a demonstration of the EPR correlations. In particular it is explained how the experimental observation of two-mode squeezing using spatially separated detectors will signify not only entanglement but EPR correlations defined in a general sense.

arXiv:quant-ph/0112038•Dec 7, 2001•2 citations

Einstein–Podolsky–Rosen-Like Correlation on a Coherent-State Basis and Inseparability of Two-Mode Gaussian States

Ryo Namiki

The strange property of the Einstein-Podolsky-Rosen (EPR) correlation between two remote physical systems is a primitive object on the study of quantum entanglement. In order to understand the entanglement in canonical continuous-variable systems, a pair of the EPR-like uncertainties is an essential tool. Here, we consider a normalized pair of the EPR-like uncertainties and introduce a state-overlap to a classically correlated mixture of coherent states. The separable condition associated with this state-overlap determines the strength of the EPR-like correlation on a coherent-state basis in order that the state is entangled. We show that the coherent-state-based condition is capable of detecting the class of two-mode Gaussian entangled states. We also present an experimental measurement scheme for estimation of the state-overlap by a heterodyne measurement and a photon detection with a feedforward operation.

arXiv:1109.0349•Journal of the Physical Society of Japan•Jan 15, 2013•4 citations

Construction of the Einstein-Podolsky-Rosen Entangled States

M. Q. Ruan, Zeng Jin-Yan

As simultaneous eigenstates of a complete set of commuting observables, construction of the Einstein-Podolsky-Rosen entangled states for a two-particle system is investigated and a sufficient condition to ensure the entanglement between a pair of commuting observables is given. It is found that for a two-particle system, four types of entangled states concerning the usually interested observables may be constructed.

Chinese Physics Letters•Aug 29, 2003•2 citations

Construction of the Einstein-Podolsky-Rosen Entangled States

M. Q. Ruan, 曾谨言

As simultaneous eigenstates of a complete set of commuting observables, construction of the Einstein-Podolsky-Rosen entangled states for a two-particle system is investigated and a sufficient condition to ensure the entangle-ment between a pair of commuting observables is given. It is found that for a two-particle system, four types of entangled states concerning the usually interested observables may be constructed.

Chinese Physics Letters•Jan 1, 2003•0 citations

Quantum states with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model

Reinhard F. Werner

A state of a composite quantum system is called classically correlated if it can be approximated by convex combinations of product states, and Einstein-Podolsky-Rosen correlated otherwise. Any classically correlated state can be modeled by a hidden-variable theory and hence satisfies all generalized Bell's inequalities. It is shown by an explicit example that the converse of this statement is false.

Physical Review A•Oct 1, 1989•4,049 citations

Einstein-Podolsky-Rosen correlations of photons: Quantum-field-theory approach

Paweł Caban

We formulate a description of Einstein-Podolsky-Rosen-type experiments with photons which is especially convenient in the discussion of questions concerning Lorentz covariance. We classify all Lorentz-covariant two-photon states with sharp momenta and define observables corresponding to measurements of the linear polarization of photons. We also calculate explicitly the Einstein-Podolsky-Rosen correlation function and coincidence rate in the scalar two-photon state.

Physical Review A•Nov 6, 2007•18 citations
For finite-dimensional systems, states satisfying perfect correlation are just maximally entangled states that play an essential role in quantum information theory. Thus perfect correlation may be a key to entanglement phenomena. For general systems, Einstein–Podolsky–Rosen type states are characterized by perfect correlation and their properties are discussed. Conditions equivalent to perfect correlation are found. As an application of perfect correlation, all Einstein–Podolsky–Rosen type states on a two-particle system are given. Unlike in finite-dimensional systems, they are generally not quasiequivalent.
A generalization of the 1935 Einstein-Podolsky-Rosen (EPR) argument for measurements with continuous variable outcomes is presented to establish criteria for the demonstration of the EPR paradox, for situations where the correlation between spatially separated subsystems is not perfect. Two types of criteria for EPR correlations are determined. The first type are based on measurements of the variances of conditional probability distributions and are necessary to reflect directly the situation of the original EPR paradox. The second weaker set of EPR criteria are based on the proven failure of (Bell-type) local realistic theories which could be consistent with a local quantum description for each subsystem. The relationship with criteria sufficient to prove entanglement is established, to show that any demonstration of EPR correlations will also signify entanglement. It is also shown how a demonstration of entanglement between two spatially separated subsystems, if not able to interpreted as a violation of a Bell-type inequality, may be interpreted as a demonstration of the EPR correlations. In particular it is explained how the experimental observation of two-mode squeezing using spatially separated detectors will signify not only entanglement but EPR correlations defined in a general sense.
The strange property of the Einstein-Podolsky-Rosen (EPR) correlation between two remote physical systems is a primitive object on the study of quantum entanglement. In order to understand the entanglement in canonical continuous-variable systems, a pair of the EPR-like uncertainties is an essential tool. Here, we consider a normalized pair of the EPR-like uncertainties and introduce a state-overlap to a classically correlated mixture of coherent states. The separable condition associated with this state-overlap determines the strength of the EPR-like correlation on a coherent-state basis in order that the state is entangled. We show that the coherent-state-based condition is capable of detecting the class of two-mode Gaussian entangled states. We also present an experimental measurement scheme for estimation of the state-overlap by a heterodyne measurement and a photon detection with a feedforward operation.