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Related papers: Separability from Spectrum for Qubit-Qudit States

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In this paper we present the necessary and sufficient conditions of separability for multipartite pure states. These conditions are very simple, and they don't require Schmidt decomposition or tracing out operations. We also give a…

Quantum Physics · Physics 2012-05-08 D. Li , H. Huang , X. Li

We study separability properties in a 5-dimensional set of states of quantum systems composed of three subsystems of equal but arbitrary finite Hilbert space dimension. These are the states, which can be written as linear combinations of…

Quantum Physics · Physics 2007-05-23 T. Eggeling , R. F. Werner

We give a separability criterion for three qubit states in terms of diagonal and anti-diagonal entries. This gives us a complete characterization of separability when all the entries are zero except for diagonal and anti-diagonals. The…

Quantum Physics · Physics 2017-09-13 Lin Chen , Kyung Hoon Han , Seung-Hyeok Kye

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

One of the most important problems in quantum information is the separability problem, which asks whether a given quantum state is separable. We investigate multipartite states of rank at most four which are PPT (i.e., all their partial…

Quantum Physics · Physics 2015-06-12 Lin Chen , Dragomir Z. Djokovic

We study separability properties in a 5-dimensional set of states of quantum systems composed of three subsystems of equal but arbitrary finite Hilbert space dimension d. These are the states, which can be written as linear combinations of…

Quantum Physics · Physics 2009-11-06 T. Eggeling , R. F. Werner

Usual separability criteria applicable to distinguishable particles are not applicable to identical particles. Here we show that Partial transposition and symmetrization (or anti symmetrization) of density matrix of bipartite boson systems…

Quantum Physics · Physics 2015-01-26 Pranav P. , M. Ravendranadhan

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

We give separability criteria for general multi-qubit states in terms of diagonal and anti-diagonal entries. We define two numbers which are obtained from diagonal and anti-diagonal entries, respectively, and compare them to get criteria.…

Quantum Physics · Physics 2018-12-10 Kil-Chan Ha , Kyung Hoon Han , Seung-Hyeok Kye

Absolutely separable states $\varrho$ remain separable under arbitrary unitary transformations $U \varrho U^{\dag}$. By example of a three qubit system we show that in multipartite scenario neither full separability implies bipartite…

Quantum Physics · Physics 2017-08-21 Sergey N. Filippov , Kamil Yu. Magadov , Maria Anastasia Jivulescu

We reduce the question whether a given quantum mixed state is separable or entangled to the problem of existence of a certain full family of commuting normal matrices whose matrix elements are partially determined by components of the pure…

Quantum Physics · Physics 2009-11-13 Jan Samsonowicz , Marek Kus , Maciej Lewenstein

We study the quantum separability problem by using general symmetric informationally complete measurements and present separability criteria for both $d$-dimensional bipartite and multipartite systems. The criterion for bipartite quantum…

Quantum Physics · Physics 2015-06-09 Bin Chen , Tao Li , Shao-Ming Fei

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

Substantial progress has recently been reported in the determination of the Hilbert-Schmidt (HS) separability probabilities for two-qubit and qubit-qutrit (real, complex and quaternionic) systems. An important theoretical concept employed…

Quantum Physics · Physics 2010-06-14 Paul B. Slater

We give a constructive proof that all mixed states of N qubits in a sufficiently small neighborhood of the maximally mixed state are separable. The construction provides an explicit representation of any such state as a mixture of product…

Quantum Physics · Physics 2009-10-31 S. L. Braunstein , C. M. Caves , R. Jozsa , N. Linden , S. Popescu , R. Schack

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 study the noisy GHZ-W mixture. We demonstrate some necessary but not sufficient criteria for different classes of separability of these states. It turns out that the partial transposition criterion of Peres and the criteria of G\"uhne…

Quantum Physics · Physics 2015-03-17 Szilárd Szalay

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

We consider the separability of rank two quantum states on multiple quantum spaces with different dimensions. The sufficient and necessary conditions for separability of these multiparty quantum states are explicitly presented. A…

Quantum Physics · Physics 2007-05-23 Shao-Ming Fei , Xiu-Hong Gao , Xiao-Hong Wang , Zhi-Xi Wang , Ke Wu

Quantum state elimination measurements tell us what states a quantum system does not have. This is different from state discrimination, where one tries to determine what the state of a quantum system is, rather than what it is not. Apart…