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Related papers: Separability of Multi-Partite Quantum States

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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

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

The separability problem is formulated in terms of a characterization of a single entanglement witness. More specifically, we show that any (in general multipartite) state \varrho is separable if and only if a specially constructed…

Quantum Physics · Physics 2016-08-17 Piotr Badziąg , Paweł Horodecki , Ryszard Horodecki , Remigiusz Augusiak

We study the measurement for the unambiguous discrimination of two mixed quantum states that are described by density operators $\rho_1$ and $\rho_2$ of rank d, the supports of which jointly span a 2d-dimensional Hilbert space. Based on two…

Quantum Physics · Physics 2009-11-13 Ulrike Herzog

We derive a separability criterion for bipartite quantum systems which generalizes the already known criteria. It is based on observables having generic commutation relations. We then discuss in detail the relation among these criteria.

Quantum Physics · Physics 2009-11-07 Vittorio Giovannetti , Stefano Mancini , David Vitali , Paolo Tombesi

We study a separability problem suggested by mathematical description of bipartite quantum systems. We consider Hermitian 2-forms on the tensor product $H=K\otimes L$, where $K,L$ are finite dimensional complex spaces. Inspired by quantum…

Mathematical Physics · Physics 2010-01-11 Bronisław Jakubczyk , Gabriel Pietrzkowski

We introduce a class of states so-called semi-SSPPT (semi super strong positive partial transposition) states in infinite-dimensional bipartite systems by the Cholesky decomposition in terms of operator matrices and show that every…

Quantum Physics · Physics 2019-02-01 Jinchuan Hou , Jinfei Chai

We present a generalized partial transposition separability criterion for the density matrix of a multipartite quantum system. This criterion comprises as special cases the famous Peres-Horodecki criterion and the recent realignment…

Quantum Physics · Physics 2009-11-07 Kai Chen , Ling-An Wu

We give a criterion for a positive mapping on the space of operators on a Hilbert space to be indecomposable. We show that this criterion can be applied to two families of positive maps. These families of maps can then be used to form…

Quantum Physics · Physics 2007-05-23 William Hall

We study the separability of symmetric bipartite quantum states and show that a single correlation measurement is sufficient to detect the entanglement of any bipartite symmetric state with a non-positive partial transpose. We also discuss…

Quantum Physics · Physics 2010-02-24 Geza Toth , Otfried Gühne

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

Motivated by the Kronecker product approximation technique, we have developed a very simple method to assess the inseparability of bipartite quantum systems, which is based on a realigned matrix constructed from the density matrix. For any…

Quantum Physics · Physics 2007-05-23 Kai Chen , Ling-An Wu

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 introduce a sequence of numerical tests that can determine the entanglement or separability of a state even when there is not enough information to completely determine its density matrix. Given partial information about the state in the…

Quantum Physics · Physics 2012-12-14 Federico M. Spedalieri

We investigate the problem of finding the optimal convex decomposition of a bipartite quantum state into a separable part and a positive remainder, in which the weight of the separable part is maximal. This weight is naturally identified…

Quantum Physics · Physics 2010-07-28 Guo Chuan Thiang

We propose a sufficient and necessary separability criterion for pure states in multipartite and high dimensional systems. Its main advantage is operational and computable. The obvious expressions of this criterion can be given out by the…

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

Separability and entanglement for n-qubits systems are quantified by using Hilbert-Schmidt (HS) decompositions in which the density matrices are decomposed into various terms representing certain one qubit, two-qubits,and larger qubits…

Quantum Physics · Physics 2016-02-23 Y. Ben-Aryeh

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

Symmetry plays an important role in the field of quantum mechanics. In this paper, we consider a subclass of symmetric quantum states in the multipartite system $N^{\otimes d}$, namely, the completely symmetric states, which are invariant…

Quantum Physics · Physics 2019-03-27 Lin Chen , Delin Chu , Lilong Qian , Yi Shen

The quantum separability problem consists in deciding whether a bipartite density matrix is entangled or separable. In this work, we propose a machine learning pipeline for finding approximate solutions for this NP-hard problem in…

Quantum Physics · Physics 2023-12-12 Balthazar Casalé , Giuseppe Di Molfetta , Sandrine Anthoine , Hachem Kadri