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Related papers: NPT Bound Entanglement- The Problem Revisited

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Bipartite entangled quantum states with a positive partial transpose (PPT), i.e., PPT entangled states, are usually considered very weakly entangled. Since no pure entanglement can be distilled from them, they are also called bound…

Quantum Physics · Physics 2021-08-26 Károly F. Pál , Géza Tóth , Erika Bene , Tamás Vértesi

We study the stability of NPT property of an arbitrary pure entangled state under the mixture of arbitrary pure separable states. For bipartite pure states with Schmidt number $n$ $(n>1)$ which is NPT, we show that this state is still NPT…

Quantum Physics · Physics 2015-09-04 Bobo Hua , Xiu-Hong Gao , Ming-Jing Zhao , Shao-Ming Fei

It is very crucial to know that whether the quantum state generated in the experiment is entangled or not. In the literature, this topic was studied extensively and researchers proposed different approaches for the detection of mixed…

Quantum Physics · Physics 2023-05-02 Anu Kumari , Satyabrata Adhikari

It is known that beyond $2 \otimes 2$ and $2 \otimes 3$ dimensional quantum systems, Peres-Hordecki criterion is no longer sufficient as an entanglement detection criterion as there are entangled states with both positive and negative…

Quantum Physics · Physics 2021-06-01 Rounak Mundra , Sabuj Chattopadhyay , Indranil Chakrabarty , Nirman Ganguly

With a probability of success of $95 \%$ we solve the separability problem for Bell diagonal qutrit states with positive partial transposition (PPT). The separability problem, i.e. distinguishing separable and entangled states, generally…

Quantum Physics · Physics 2022-09-22 Christopher Popp , Beatrix C. Hiesmayr

The problem of bound entanglement detection is a challenging aspect of quantum information theory for higher dimensional systems. Here, we propose an indecomposable positive map for two-qutrit systems, which is shown to generate a class of…

Genuinely entangled subspaces are a class of subspaces in the multipartite Hilbert spaces that are composed of only genuinely entangled states. They are thus an interesting object of study in the context of multipartite entanglement. Here…

Quantum Physics · Physics 2023-02-15 Owidiusz Makuta , Błażej Kuzaka , Remigiusz Augusiak

A deep understanding of quantum entanglement is vital for advancing quantum technologies. The strength of entanglement can be quantified by counting the degrees of freedom that are entangled, which results in a quantity called Schmidt…

Quantum Physics · Physics 2024-02-21 Robin Krebs , Mariami Gachechiladze

As a consequence of having a positive partial transpose, bound entangled states lack many of the properties otherwise associated with entanglement. It is therefore interesting to identify properties that distinguish bound entangled states…

Quantum Physics · Physics 2016-09-08 Holger F. Hofmann

We study bipartite entangled states in arbitrary dimensions and obtain different bounds for the entanglement measures in terms of teleportation fidelity. We find that there is a simple relation between negativity and teleportation fidelity…

Quantum Physics · Physics 2014-03-12 Sk. Sazim , Satyabrata Adhikari , Subhashish Banerjee , T. Pramanik

The entanglement in a pure state of N qudits (d-dimensional distinguishable quantum particles) can be characterised by specifying how entangled its subsystems are. A generally mixed subsystem of m qudits is obtained by tracing over the…

Quantum Physics · Physics 2009-11-07 Vivien M Kendon , Karol Zyczkowski , William J Munro

A definition of the Schmidt number of a state of an infinite dimensional bipartite quantum system is given and properties of the corresponding family of Schmidt classes are considered. The existence of states with a given Schmidt number…

Quantum Physics · Physics 2013-04-26 M. E. Shirokov

We first show that partial transposition for pure and mixed two-particle states in a discrete $N$-dimensional Hilbert space is equivalent to a change in sign of the momentum of one of the particles in the Wigner function for the state. We…

Quantum Physics · Physics 2016-01-19 Y. B. Band , Pier A. Mello

We construct $3\otimes 3$ PPT entangled edge states with maximal ranks, to complete the classification of $3\otimes 3$ PPT entangled edge states by their types. The ranks of the states and their partial transposes are 8 and 6, respectively.…

Quantum Physics · Physics 2015-06-04 Seung-Hyeok Kye , Hiroyuki Osaka

Although quantum entanglement is an important resource, its characterization is quite challenging. The partial transposition is a common method to detect bipartite entanglement. In this paper, the authors study the…

Quantum Physics · Physics 2024-05-01 Lin Zhang , Ming-Jing Zhao , Lin Chen , Hua Xiang , Yi Shen

The basic question that is addressed in this paper is finding the closest separable state for a given entangled state, measured with the Hilbert Schmidt distance. While this problem is in general very hard, we show that the following…

Quantum Physics · Physics 2009-11-07 Frank Verstraete , Jeroen Dehaene , Bart De Moor

We construct ($d\times d$)-dimensional bound entangled states, which violate, for any $d>2$, a bipartite Bell inequality introduced in this paper. We conjecture that the proposed class of Bell inequalities acts as a dimension witness for…

Quantum Physics · Physics 2017-12-29 Karoly F Pal , Tamas Vertesi

We consider a quantum system of n qudits and the Clebsch-Gordan decomposition of the associated Hilbert space. In this decomposition, one of the subspaces is the so-called symmetric subspace or symmetric sector, that is, the subspace of all…

Quantum Physics · Physics 2025-07-09 Domenico D'Alessandro

Entanglement is at the heart of most quantum information tasks, and therefore considerable effort has been made to find methods of deciding the entanglement content of a given bipartite quantum state. Here, we prove a fundamental limitation…

Quantum Physics · Physics 2016-06-15 Claudio Carmeli , Teiko Heinosaari , Antti Karlsson , Jussi Schultz , Alessandro Toigo

We analyze entanglement and nonlocal properties of the convex set of symmetric $N$-qubits states which are diagonal in the Dicke basis. First, we demonstrate that within this set, positivity of partial transposition (PPT) is necessary and…

Quantum Physics · Physics 2017-05-03 Ruben Quesada , Swapan Rana , Anna Sanpera