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Related papers: Inclusion relations among separability criteria

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We study families of positive and completely positive maps acting on a bipartite system $\mathbb{C}^M\otimes \mathbb{C}^N$ (with $M\leq N$). The maps have a property that when applied to any state (of a given entanglement class) they result…

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

Employing a recently proposed separability criterion we develop analytical lower bounds for the concurrence and for the entanglement of formation of bipartite quantum systems. The separability criterion is based on a nondecomposable…

Quantum Physics · Physics 2007-05-23 Heinz-Peter Breuer

We present separability criteria based on local symmetric measurements. These experimental plausible criteria are shown to be more efficient in detecting entanglement than the current counterparts by detailed examples. Furthermore, we…

Quantum Physics · Physics 2025-12-30 Yu Lu , Hao-Fan Wang , Meng Su , Zhi-Xi Wang , Shao-Ming Fei

We construct a density matrix whose elements are written in terms of expectation values of non-Hermitian operators and their products for arbitrary dimensional bipartite states. We then show that any expression which involves matrix…

Quantum Physics · Physics 2015-06-23 N. Ananth , V. K. Chandrasekar , M. Senthilvelan

We extend the classification of mixed states of quantum systems composed of arbitrary number of subsystems of arbitrary dimensions. This extended classification is complete in the sense of partial separability and gives 1+18+1 partial…

Quantum Physics · Physics 2012-10-03 Szilárd Szalay , Zoltán Kökényesi

We study the separability of bipartite quantum systems in arbitrary dimensions based on the Bloch representation of density matrices. We present two separability criteria for quantum states in terms of the matrices $T_{\alpha\beta}(\rho)$…

Quantum Physics · Physics 2023-05-11 Xue-Na Zhu , Jing Wang , Gui Bao , Ming Li , Shu-Qian Shen , Shao-Ming Fei

We present a new set of inseparabilty inequalities to detect entanglement in $N$-spin states. These are based on negative partial transposition and involve collective spin-spin correlations of any two partitions of the entire system. They…

Quantum Physics · Physics 2016-08-08 Asoka Biswas

We provide a necessary and sufficient condition for separability of Gaussian states of bipartite systems of arbitrarily many modes. The condition provides an operational criterion since it can be checked by simple computation. Moreover, it…

Quantum Physics · Physics 2009-11-07 G. Giedke , B. Kraus , M. Lewenstein , J. I. Cirac

Based on the ranks of reduced density matrices, we derive necessary conditions for the separability of multiparticle arbitrary-dimensional mixed states, which are equivalent to sufficient conditions for entanglement. In a similar way we…

Quantum Physics · Physics 2007-05-23 Bo Chong , Hellmut Keiter , Joachim Stolze

We present a framework for deciding whether a quantum state is separable or entangled using covariance matrices of locally measurable observables. This leads to the covariance matrix criterion as a general separability criterion. We…

Quantum Physics · Physics 2008-12-03 Oleg Gittsovich , Otfried Gühne , Philipp Hyllus , Jens Eisert

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

We derive a family of necessary separability criteria for finite-dimensional systems based on inequalities for variances of observables. We show that every pure bipartite entangled state violates some of these inequalities. Furthermore, a…

Quantum Physics · Physics 2016-09-08 Otfried Guehne

As one of the most profound features of quantum mechanics, entanglement is a vital resource for quantum information processing. Inspired by the recent work on PT-moments and separablity [Phys. Rev. Lett. {\bf 127}, 060504 (2021)], we…

Quantum Physics · Physics 2024-02-21 Xiaofen Huang , Naihuan Jing

A new hierarchy of separability conditions for bipartite states is obtained. All the conditions in the hierarchy are necessary for separability. The conditions are expressed in terms of higher powers of the density operator of the bipartite…

Quantum Physics · Physics 2010-06-10 S. Sivakumar

Quantum entanglement has been regarded as one of the key physical resources in quantum information sciences. However, the determination of whether a mixed state is entangled or not is generally a hard issue, even for the bipartite system.…

Quantum Physics · Physics 2018-02-15 Jun-Li Li , Cong-Feng Qiao

We present a necessary and sufficient condition for the separability of multipartite quantum states, this criterion also tells us how to write a multipartite separable state as a convex sum of separable pure states. To work out this…

Quantum Physics · Physics 2009-11-06 Shengjun Wu , Xuemei Chen , Yongde Zhang

In a recent paper (quant-ph/0102133) Chen, Liang, Li and Huang suggest a necessary and sufficient separability criterion, which is supposedly practical in judging the separability of any mixed state. In this note we briefly recapitulate…

Quantum Physics · Physics 2007-05-23 T. Eggeling , K. G. H. Vollbrecht , M. M. Wolf

We compute the probability that a bipartite quantum state is separable by Monte Carlo sampling. This is carried out for rebits, qubits and quaterbits. We sampled $5\times 10^{11}$ points for each of these three cases. The results strongly…

Quantum Physics · Physics 2016-11-22 Jianjia Fei , Robert Joynt

We obtain a collection of necessary (sufficient) conditions for a bipartite system of qubits to be separable (entangled), which are based on the Landau-Pollak formulation of the uncertainty principle. These conditions are tested, and…

Quantum Physics · Physics 2009-11-11 Julio I. de Vicente , Jorge Sánchez-Ruiz