English
Related papers

Related papers: Estimating multipartite entanglement measures

200 papers

Characterization of the multipartite mixed state entanglement is still a challenging problem. Since due to the fact that the entanglement for the mixed states, in general, is defined by a convex-roof extension. That is the entanglement…

Quantum Physics · Physics 2016-11-30 M. A. Jafarizadeh , M. Yahyavi , A. Heshmati , N. Karimi , A. Mohamadzadeh , F. Eghbalifam , S. Nami

Multipartite entanglement is the premier resource for quantum technologies. Yet, its exact quantification in the laboratory is notoriously challenging, typically requiring the full knowledge of high dimensional quantum states. Here, we…

Quantum Physics · Physics 2026-05-05 Francois Payn , Davide Girolami

We give an explicit expression for the geometric measure of entanglement for three qubit states that are linear combinations of four orthogonal product states. It turns out that the geometric measure for these states has three different…

Quantum Physics · Physics 2008-09-03 Levon Tamaryan , DaeKil Park , Jin-Woo Son , Sayatnova Tamaryan

We construct an important missing piece in the entanglement theory of pure three-qubit states, which is a polynomial measure of W-entanglement, working in parallel to the three-tangle, which is a polynomial measure of GHZ-entanglement, and…

Quantum Physics · Physics 2025-12-12 Szilárd Szalay

Recently a proper genuine multipartite entanglement (GME) measure has been found for three-qubit pure states [see Xie and Eberly, Phys. Rev. Lett. 127, 040403 (2021)], but capturing useful entanglement measures for mixed states has remained…

I calculate the mixed threetangle $\tau_3[\rho]$ for the reduced density matrices of the four-qubit representant states found in Phys. Rev. A {\bf 65}, 052112 (2002). In most of the cases, the convex roof is obtained, except for one class,…

Quantum Physics · Physics 2016-09-05 Andreas Osterloh

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings (see Shimony 1995 and…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Paul M. Goldbart

Closed formulae for upper bound on three tangles of three-qubit reduced states in terms of three-qubit invariant polynomials of pure four-qubit states are obtained. Our results offer tighter constraints on total three-way entanglement of a…

Quantum Physics · Physics 2017-06-07 S. Shelly Sharma , N. K. Sharma

If only limited control over a multiparticle quantum system is available, a viable method to characterize correlations is to perform random measurements and consider the moments of the resulting probability distribution. We present…

Quantum Physics · Physics 2021-04-23 Satoya Imai , Nikolai Wyderka , Andreas Ketterer , Otfried Gühne

We derive a simple lower bound on the geometric measure of entanglement for mixed quantum states in the case of a general multipartite system. The main ingredient of the presented derivation is the triangle inequality applied to the root…

Quantum Physics · Physics 2016-05-11 Łukasz Rudnicki , Zbigniew Puchała , Paweł Horodecki , Karol Zyczkowski

In this paper we describe how three qubit entanglement can be analyzed with local measurements. For this purpose we decompose entanglement witnesses into operators which can be measured locally. Our decompositions are optimized in the…

Quantum Physics · Physics 2017-02-13 Otfried Gühne , Philipp Hyllus

The distribution of entanglement in a multiparty system can be described through the principles of monogamy or polygamy. Monogamy is a fundamental characteristic of entanglement that restricts its distribution among several number of…

We study the loss of entanglement of bipartite state subjected to discarding or measurement of one qubit. Examining the behavior of different entanglement measures, we find that entanglement of formation, entanglement cost, and logarithmic…

Quantum Physics · Physics 2009-11-10 Karol Horodecki , Michal Horodecki , Pawel Horodecki , Jonathan Oppenheim

An important problem in quantum information theory is the quantification of entanglement in multipartite mixed quantum states. In this work, a connection between the geometric measure of entanglement and a distance measure of entanglement…

Quantum Physics · Physics 2010-12-08 Alexander Streltsov , Hermann Kampermann , Dagmar Bruß

In recent years, analysis methods for quantum states based on randomized measurements have been investigated extensively. Still, in the experimental implementations these methods were typically used for characterizing strongly entangled…

In this research, the entanglement within two entangled n-qubit systems is analyzed using the one-tangle, two-tangle, and {\pi}-tangle. The findings indicate that for certain quantum states, such as the generalized W state, where the…

Quantum Physics · Physics 2026-05-29 Reza Hamzehofi

Any pure three-qubit state is uniquely characterized by one phase and four positive parameters. The geometric measure of entanglement as a function of state parameters can have different expressions. Each of expressions has its own…

Quantum Physics · Physics 2009-09-08 Sayatnova Tamaryan , Hungsoo Kim , Mu-Seong Kim , Kap Soo Jang , DaeKil Park

We present a multipartite entanglement measure for $N$-qudit pure states, using the norm of the correlation tensor which occurs in the Bloch representation of the state. We compute this measure for important class of $N$-qutrit pure states,…

Quantum Physics · Physics 2010-01-01 Ali Saif M. Hassan , Pramod S. Joag

Exploring an analytical expression for the convex roof of the pure state squared concurrence for rank 2 mixed states the entanglement of a system of three particles under decoherence is studied, using the monogamy inequality for mixed…

Quantum Physics · Physics 2009-08-28 Thiago R. de Oliveira

We extend the concept of the negativity, a good measure of entanglement for bipartite pure states, to mixed states by means of the convex-roof extension. We show that the measure does not increase under local quantum operations and…

Quantum Physics · Physics 2009-11-10 Soojoon Lee , Dong Pyo Chi , Sung Dahm Oh , Jaewan Kim