scispace - formally typeset
Open AccessJournal ArticleDOI

Entangled three-qubit states without concurrence and three-tangle.

TLDR
By studying the Coffman-Kundu-Wootters inequality, it is found that, while the amounts of inequivalent entanglement types strictly add up for pure states, this "monogamy" can be lifted for mixed states by virtue of vanishing tangle measures.
Abstract
We provide a complete analysis of mixed three-qubit states composed of a Greenberger-Horne-Zeilinger state and a $W$ state orthogonal to the former. We present optimal decompositions and convex roofs for the three-tangle. Further, we provide an analytical method to decide whether or not an arbitrary rank-2 state of three qubits has vanishing three-tangle. These results highlight intriguing differences compared to the properties of two-qubit mixed states, and may serve as a quantitative reference for future studies of entanglement in multipartite mixed states. By studying the Coffman-Kundu-Wootters inequality we find that, while the amounts of inequivalent entanglement types strictly add up for pure states, this ``monogamy'' can be lifted for mixed states by virtue of vanishing tangle measures.

read more

Citations
More filters
Journal ArticleDOI

Quantum entanglement

TL;DR: In this article, the basic aspects of entanglement including its characterization, detection, distillation, and quantification are discussed, and a basic role of entonglement in quantum communication within distant labs paradigm is discussed.
Journal ArticleDOI

Entanglement detection

TL;DR: In this article, the basic elements of entanglement theory for two or more particles and verification procedures, such as Bell inequalities, entangle witnesses, and spin squeezing inequalities, are discussed.
Journal ArticleDOI

A classification of entanglement in three-qubit systems

TL;DR: In this paper, a classification of three-qubit states based on their three qubits and reduced two qubits entanglement was presented, and the three qubit states were related with sets of equivalence classes under local unitary operations.
Journal ArticleDOI

Quantifying entanglement resources

TL;DR: In this article, the authors present an overview of the quantitative theory of single-copy entanglement in finite-dimensional quantum systems, and emphasize the point of view that different entonglement measures quantify different types of resources.
Journal ArticleDOI

Geometric measure of entanglement for symmetric states

TL;DR: In this article, the closest product state to a symmetric entangled multiparticle state is shown to be symmetric, and it is shown that the symmetric state can be chosen to be either symmetric or not symmetric.
References
More filters
Journal ArticleDOI

Entanglement of Formation of an Arbitrary State of Two Qubits

TL;DR: In this article, an explicit formula for the entanglement of formation of a pair of binary quantum objects (qubits) as a function of their density matrix was conjectured.
Journal ArticleDOI

Mixed State Entanglement and Quantum Error Correction

TL;DR: It is proved that an EPP involving one-way classical communication and acting on mixed state M (obtained by sharing halves of Einstein-Podolsky-Rosen pairs through a channel) yields a QECC on \ensuremath{\chi} with rate Q=D, and vice versa, and it is proved Q is not increased by adding one- way classical communication.
Journal ArticleDOI

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

TL;DR: Any classically correlated state can be modeled by a hidden-variable theory and hence satisfies all generalized Bell's inequalities and the converse of this statement is false.
Journal ArticleDOI

Three qubits can be entangled in two inequivalent ways

TL;DR: In this paper, it was shown that the Greenberger-Horne-Zeilinger state and a W state retain maximally bipartite entanglement when any one of the three qubits is traced out.
Journal ArticleDOI

Concentrating partial entanglement by local operations

TL;DR: Any pure or mixed entangled state of two systems can be produced by two classically communicating separated observers, drawing on a supply of singlets as their sole source of entanglement.
Related Papers (5)