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Related papers: Sufficient separability criteria and linear maps

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In this paper, we discuss some general connections between the notions of positive map, weak majorization and entropic inequalities in the context of detection of entanglement among bipartite quantum systems. First, basing on the fact that…

Quantum Physics · Physics 2009-07-09 Remigiusz Augusiak , Julia Stasińska

We show that pure states of multipartite quantum systems are multiseparable (i.e. give separable density matrices on tracing any party) if and only if they have a generalized Schmidt decomposition. Implications of this result for the…

Quantum Physics · Physics 2009-10-31 Ashish V. Thapliyal

The detection of entanglement in a bipartite state is a crucial issue in quantum information science. Based on realignment of density matrices and the vectorization of the reduced density matrices, we introduce a new set of separability…

Quantum Physics · Physics 2024-12-09 Yu Lu , Zhong-Xi Shen , Shao-Ming Fei , Zhi-Xi Wang

Inspired by the `computable cross norm' or `realignment' criterion, we propose a new point of view about the characterization of the states of bipartite quantum systems. We consider a Schmidt decomposition of a bipartite density operator.…

Quantum Physics · Physics 2008-09-16 Cosmo Lupo , Paolo Aniello , Antonello Scardicchio

After introducing the partially separable concept, we proved the equivalence between the partial separability of a given $m$-partite subsystem with $m$ qubits and the purity of states of this $m$-partite subsystem for a pure state in…

Quantum Physics · Physics 2007-05-23 An Min Wang

We present a necessary and sufficient product criterion for bipartite quantum states based on the rank of realignment matrix of density matrix. Then, this approach is generalized to multipartite systems. We first introduce the concept of…

Quantum Physics · Physics 2018-02-27 Xianfei Qi , Ting Gao , Fengli Yan

We introduce a 3-parameter class of maps acting on a bipartite system that are a natural generalisation of the depolarizing channel (and include it as a special case). Then, we find the exact regions of the parameter space that…

Quantum Physics · Physics 2017-06-02 Ludovico Lami , Marcus Huber

We study certain quantum states for which the PPT criterion is both sufficient and necessary for separability. A class of $n\times n$ bipartite mixed states is presented and the conditions of PPT for these states are derived. The separable…

Quantum Physics · Physics 2014-01-07 Ting-Gui Zhang , Xiaofen Huang , Xianqing Li-Jost , Naihuan Jing , Shao-Ming Fei

We use operators from generalized equiangular measurements to construct positive maps. Their positivity follows from the inequality for indices of coincidence corresponding to few equiangular tight frames. These maps give rise to…

Quantum Physics · Physics 2025-11-18 Katarzyna Siudzińska

The positive partial transpose test is one of the main criteria for detecting entanglement, and the set of states with positive partial transpose is considered as an approximation of the set of separable states. However, we do not know to…

Quantum Physics · Physics 2015-05-13 Salman Beigi , Peter W. Shor

The Schmidt decomposition is an important tool in the study of quantum systems especially for the quantification of the entanglement of pure states. However, the Schmidt decomposition is only unique for bipartite pure states, and some…

Quantum Physics · Physics 2009-02-04 Mark S. Byrd , Gavin K. Brennen

Separability from the spectrum is a significant and ongoing research topic in quantum entanglement. In this study, we investigate properties related to absolute separability from the spectrum in qudits-qudits states in the bipartite states…

Quantum Physics · Physics 2024-08-22 Liang Xiong , Nung-Sing Sze

A group of symmetric operators are introduced to carry out the separability criterion for bipartite and multipartite quantum states. Every symmetric operator, represented by a symmetric matrix with only two nonzero elements, and their…

Quantum Physics · Physics 2012-12-04 Jie-Hui Huang , Li-Yun Hu , Lei Wang , Shi-Yao Zhu

We fully characterize bipartite entanglement-annihilating (EA) channels that destroy entanglement of any state shared by subsystems and, thus, should be avoided in any entanglement-enabled experiment. Our approach relies on extending the…

Quantum Physics · Physics 2013-09-17 S. N. Filippov , M. Ziman

We provide a partial classification of positive linear maps in matrix algebras which is based on a family of spectral conditions. This construction generalizes celebrated Choi example of a map which is positive but not completely positive.…

Quantum Physics · Physics 2009-11-13 Dariusz Chruscinski , Andrzej Kossakowski

A new criterion necessary and sufficient for the separability of pure bipartite systems for arbitrary finite dimensions is demonstrated; and the corresponding finer quantitative measures or characterizations of entanglement (beyond mere…

Quantum Physics · Physics 2013-04-22 Che-Hsu Li

This paper present a geometric diagram of a separable state: If a mixed state $\sigma $ is separable, there are $2^{nS(\sigma)}$ linearly independant product vectors which span the same Hilbert space as the $2^{nS(\sigma)}$ ``likely''…

Quantum Physics · Physics 2007-05-23 Ping Xing Chen , Cheng Zu Li

We present separability criteria for both bipartite and multipartite quantum states. These criteria include the criteria based on the correlation matrix and its generalized form as special cases. We show by detailed examples that our…

Quantum Physics · Physics 2014-02-19 Ming Li , Jing Wang , Shao-Ming Fei , Xianqing Li-Jost

The purpose of this paper is to obtain a sufficient and necessary condition as a criteria to test whether an arbitrary multipartite state is entangled or not. Based on the tensor expression of a multipartite pure state, the paper shows that…

Quantum Physics · Physics 2007-05-23 Chang-shui Yu , He-shan Song

We investigate the detection of entanglement in $n$-partite quantum states. We obtain practical separability criteria to identify genuinely entangled and non-separable mixed quantum states. No numerical optimization or eigenvalue evaluation…

Quantum Physics · Physics 2010-12-15 Ting Gao , Yan Hong