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

arXiv:quant-ph/0611229 · Physical Review A

Lower bounds on concurrence and separability conditions

Julio I. de Vicente

Published May 17, 2007• 126 citations
arXivHTMLPDF

Abstract

We obtain analytical lower bounds on the concurrence of bipartite quantum systems in arbitrary dimensions related to the violation of separability conditions based on local uncertainty relations and on the Bloch representation of density matrices. We also illustrate how these results complement and improve those recently derived [Chen, Albeverio, and Fei, Phys. Rev. Lett. 95, 040504 (2005)] by considering the Peres-Horodecki and the computable cross-norm or realignment criteria.

DOI
10.1103/physreva.75.052320

Related papers

A Lower Bound on Concurrence

Liguo Liu, Tian Chenglin, Ping‐Xing Chen +1 more

We derive an analytical lower bound on the concurrence for bipartite quantum systems with an improved computable cross norm or realignment criterion and an improved positive partial transpose criterion respectively. Furthermore we demonstrate that our bound is better than that obtained from the local uncertainty relations criterion with optimal local orthogonal observables which is known as one of the best estimations of concurrence.

Chinese Physics Letters•Jun 1, 2009•11 citations

Lower bound of concurrence based on positive maps

Xiaosheng Li, Xiu-Hong Gao, Shao-Ming Fei

We study the concurrence of arbitrary dimensional bipartite quantum systems. An explicit analytical lower bound of concurrence is obtained which detects entanglement for some quantum states better than some well-known separability criteria and improves the lower bounds, such as from the positive partial transposition, realignment criteria, and Breuer's entanglement witness.

arXiv:1104.1000•Physical Review A•Mar 25, 2011•17 citations

Concurrence of Arbitrary Dimensional Bipartite Quantum States

Kai Chen, Sergio A Albeverio, Shao-Ming Fei

We derive an analytical lower bound for the concurrence of a bipartite quantum state in arbitrary dimension. A functional relation is established relating concurrence, the Peres-Horodecki criterion, and the realignment criterion. We demonstrate that our bound is exact for some mixed quantum states. The significance of our method is illustrated by giving a quantitative evaluation of entanglement for many bound entangled states, some of which fail to be identified by the usual concurrence estimation method.

arXiv:quant-ph/0506136•Physical Review Letters•Jul 22, 2005•315 citations

Separability criteria and lower bounds of entanglement via realignment

Yuhang Xie, Yanjun Chu, Shao-Ming Fei

The detection and quantification of quantum entanglement are central problems in quantum information science. Based on the realignment of density matrices and the vectorization of reduced density matrices, we construct a family of enhanced separability criteria for bipartite and multipartite quantum systems. Our criteria recover the previously proposed realignment-based criteria as special cases and detect more entanglement than the earlier ones. Moreover, we derive tighter lower bounds for the concurrence and the convex-roof extended negativity, criteria for detecting the genuine tripartite entanglement, and lower bounds on genuine-multipartite-entanglement concurrence. The advantages of our results are demonstrated with detailed examples.

quant-pharXiv:2610.15664•Oct 13, 2026•0 citations

Trace norm related to concurrence

Wei Cheng

By investigating the property of the trace norm which appeared in the analytical lower bound for the concurrence of arbitrary dimensional bipartite quantum states [Phys. Rev. Lett. 95, 040504 (2005)], we demonstrate the limitation of the bound in that paper and provide several concrete examples.

IEEE Congress on Evolutionary Computation (CEC)•Jun 1, 2008•0 citations

Separability and lower bounds of quantum entanglement based on realignment

Jiaxin Sun, Hongmei Yao, Shao-Ming Fei +1 more

The detection and estimation of quantum entanglement are the essential issues in the theory of quantum entanglement. We construct matrices based on the realignment of density matrices and the vectorization of the reduced density matrices, from which a family of separability criteria are presented for both bipartite and multipartite systems. Moreover, tighter lower bounds of concurrence and convex-roof extended negativity are derived. Criteria are also given to detect the genuine tripartite entanglement. Lower bounds of the concurrence of genuine tripartite entanglement are presented. By detailed examples we show that our results are better than the corresponding ones in identifying and estimating quantum entanglement as well as genuine multipartite entanglement.

arXiv:2405.11861•Physical Review A•Jan 8, 2025•5 citations
We obtain analytical lower bounds on the concurrence of bipartite quantum systems in arbitrary dimensions related to the violation of separability conditions based on local uncertainty relations and on the Bloch representation of density matrices. We also illustrate how these results complement and improve those recently derived [Chen, Albeverio, and Fei, Phys. Rev. Lett. 95, 040504 (2005)] by considering the Peres-Horodecki and the computable cross-norm or realignment criteria.
We derive an analytical lower bound for the concurrence of a bipartite quantum state in arbitrary dimension. A functional relation is established relating concurrence, the Peres-Horodecki criterion, and the realignment criterion. We demonstrate that our bound is exact for some mixed quantum states. The significance of our method is illustrated by giving a quantitative evaluation of entanglement for many bound entangled states, some of which fail to be identified by the usual concurrence estimation method.
The detection and quantification of quantum entanglement are central problems in quantum information science. Based on the realignment of density matrices and the vectorization of reduced density matrices, we construct a family of enhanced separability criteria for bipartite and multipartite quantum systems. Our criteria recover the previously proposed realignment-based criteria as special cases and detect more entanglement than the earlier ones. Moreover, we derive tighter lower bounds for the concurrence and the convex-roof extended negativity, criteria for detecting the genuine tripartite entanglement, and lower bounds on genuine-multipartite-entanglement concurrence. The advantages of our results are demonstrated with detailed examples.
The detection and estimation of quantum entanglement are the essential issues in the theory of quantum entanglement. We construct matrices based on the realignment of density matrices and the vectorization of the reduced density matrices, from which a family of separability criteria are presented for both bipartite and multipartite systems. Moreover, tighter lower bounds of concurrence and convex-roof extended negativity are derived. Criteria are also given to detect the genuine tripartite entanglement. Lower bounds of the concurrence of genuine tripartite entanglement are presented. By detailed examples we show that our results are better than the corresponding ones in identifying and estimating quantum entanglement as well as genuine multipartite entanglement.