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Related papers: Entanglement of 2xK quantum systems

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In contrast to abstract statistical analyses in the literature, we present a concrete physical diagrammatic model of entanglement characterization and measure with its underlying discrete phase-space physics. This paper serves as a…

Quantum Physics · Physics 2023-05-30 Felix A. Buot

Quantum entanglement plays a pivotal role in quantum information processing. Quantifying quantum entanglement is a challenging and essential research area within the field. This manuscript explores the relationships between bipartite…

Quantum Physics · Physics 2025-04-22 Ming Li , Yaru Dong , Ruiqi Zhang , Xuena Zhu , Shuqian Shen , Lei Li , Shao-Ming Fei

We present a measure of quantum entanglement which is capable of quantifying the degree of entanglement of a multi-partite quantum system. This measure, which is based on a generalization of the Schmidt rank of a pure state, is defined on…

Quantum Physics · Physics 2016-09-08 J. Eisert , H. -J. Briegel

In this paper, we study the bipartite entanglement of spin coherent states in the case of pure and mixed states. By a proper choice of the subsystem spins, the entanglement for large class of quantum systems is investigated. We generalize…

Quantum Physics · Physics 2015-06-12 K. Berrada , A. Mohammadzade , S. Abdel-Khalek , H. Eleuch , S. Salimi

We study the fully entangled fraction of quantum states. An upper bound is obtained for arbitrary dimensional bipartite systems. This bound is shown to be exact for the case of two-qubit systems. An inequality related the fully entangled…

Quantum Physics · Physics 2009-11-13 Ming Li , Shao-Ming Fei , Zhi-Xi Wang

Covariance matrices are a useful tool to investigate correlations and entanglement in quantum systems. They are widely used in continuous variable systems, but recently also for finite dimensional systems powerful entanglement criteria in…

Quantum Physics · Physics 2010-04-22 Oleg Gittsovich , Otfried Gühne

Entanglement is the central resource of quantum information processing and the precise characterization of entangled states is a crucial issue for the development of quantum technologies. This leads to the necessity of a precise,…

The problems of genuine multipartite entanglement detection and classification are challenging. We show that a multipartite quantum state is genuine multipartite entangled if the multipartite concurrence is larger than certain quantities…

Quantum Physics · Physics 2015-12-31 Ming Li , Shao-Ming Fei , Xianqing Li-Jost , Heng Fan

We present a new approach to the analysis of entanglement in smooth bipartite continuous-variable states. One or both parties perform projective filterings via preliminary measurements to determine whether the system is located in some…

Quantum Physics · Physics 2009-11-13 H. -C. Lin , A. J. Fisher

While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues…

Quantum Physics · Physics 2009-11-25 Remigiusz Augusiak , Maciej Lewenstein

We derive measurable lower bounds on concurrence of arbitrary mixed states, for both bipartite and multipartite cases. First, we construct measurable lower bonds on the purely algebraic bounds of concurrence [F. Mintert et al. (2004), Phys.…

Quantum Physics · Physics 2011-01-21 Iman Sargolzahi , Sayyed Yahya Mirafzali , Mohsen Sarbishaei

In this paper, we study the concurrence of arbitrary dimensional tripartite quantum systems. An explicit operational lower bound of concurrence is obtained in terms of the concurrence of sub-states. A given example show that our lower bound…

Quantum Physics · Physics 2017-10-31 Wei Chen , Shao-Ming Fei , Zhu-Jun Zheng

This paper presents a new measure of entanglement which can be employed for multipartite entangled systems. The classification of multipartite entangled systems based on this measure is considered. Two approaches to applying this measure to…

Quantum Physics · Physics 2018-08-20 Seyed Arash Sheikholeslam , Thomas Aaron Gulliver

We give an analytical lower bound of concurrence for both bipartite and multipartite quantum states.

Quantum Physics · Physics 2011-10-31 Zhihao Ma , Zhi-Hua Chen

We present observable lower bounds for several bipartite entanglement measures including entanglement of formation, geometric measure of entanglement, concurrence, convex-roof extended negativity, and G-concurrence. The lower bounds…

Quantum Physics · Physics 2016-10-20 Chengjie Zhang , Sixia Yu , Qing Chen , Haidong Yuan , C. H. Oh

We discuss the problem of characterizing upper bounds on entanglement in a bipartite quantum system when only the reduced density matrices (marginals) are known. In particular, starting from the known two-qubit case, we propose a family of…

The quantitative assessment of the entanglement in multipartite quantum states is, apart from its fundamental importance, a practical problem. Recently there has been significant progress in developing new methods to determine certain…

Quantum Physics · Physics 2014-03-17 Christopher Eltschka , Jens Siewert

We present a method to quantify entanglement in mixed states of highly symmetric systems. Symmetry constrains interactions between parts and predicts the degeneracies of the states. While symmetry alone produces entangled eigenstates, the…

Quantum Physics · Physics 2025-06-05 S. H. Curnoe , D. Gajera , C. Wei

We propose generalizations of concurrence for multi-partite quantum systems that can distinguish qualitatively distinct quantum correlations. All introduced quantities can be evaluated efficiently for arbitrary mixed sates.

Quantum Physics · Physics 2009-11-10 Florian Mintert , Marek Kus , Andreas Buchleitner

We give explicit expressions for entanglement measures of Werner states in arbitrary dimensions in terms of concurrence and tangle. We show that an optimal ensemble decomposition for a joint density matrix of a Werner state can achieve the…

Quantum Physics · Physics 2012-10-30 Kai Chen , Sergio Albeverio , Shao-Ming Fei