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Related papers: Some Remarks on the Entanglement Number

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We introduce a Gaussian version of the entanglement of formation adapted to bipartite Gaussian states by considering decompositions into pure Gaussian states only. We show that this quantity is an entanglement monotone under Gaussian…

Quantum Physics · Physics 2009-11-10 M. M. Wolf , G. Giedke , O. Krueger , R. F. Werner , J. I. Cirac

Multipartite entanglement is regarded as a crucial physical resource in quantum network communication. However, due to the intrinsic complexity of quantum many-body systems, identifying a multipartite entanglement measure that is both…

Quantum Physics · Physics 2025-12-10 Yu Luo , Zhihua Guo , Fanxu Meng , Chen-Ming Bai

The most simplest form of quantum network is an one dimensional quantum network with a single player in each node. In remote entanglement distribution each of the players carry out measurement at the intermediate nodes to produce an…

Quantum Physics · Physics 2023-06-27 Ganesh Mylavarapu , Indranil Chakrabarty , Kaushiki Mukherjee , Minyi Huang , Junde Wu

The notion of entanglement of quantum states is usually defined with respect to a fixed bipartition. Indeed, a global basis change can always map an entangled state to a separable one. The situation is however different when considering a…

Quantum Physics · Physics 2021-06-02 Yu Cai , Baichu Yu , Pooja Jayachandran , Nicolas Brunner , Valerio Scarani , Jean-Daniel Bancal

Based on the geometry of entangled three and two qubit states, we present the connection between the entanglement measure of the three-qubit state defined using the last Hopf fibration and the entanglement measures known as two- and…

Quantum Physics · Physics 2009-05-01 P. A. Pinilla , J. R. Luthra

Among the many facets of quantum correlations, bound entanglement has remained one the most enigmatic phenomena, despite the fact that it was discovered in the early days of quantum information. Even its detection has proven to be…

Quantum Physics · Physics 2016-09-07 Gael Sentís , Christopher Eltschka , Jens Siewert

We investigate the lower bound obtained from experimental data of a quantum state $\rho$, as proposed independently by G\"uhne et al. and Eisert et al. for mixed states of three qubits. The measure we consider is the convex-roof extended…

Quantum Physics · Physics 2010-03-04 A. Osterloh , P. Hyllus

We propose that the entanglement of mixed states is characterised properly in terms of a probability density function $\mathcal{P}(\mathcal{E})$. There is a need for such a measure since the prevalent measures (such as \textit{concurrence}…

Quantum Physics · Physics 2007-05-23 Shanthanu Bhardwaj , V. Ravishankar

We prove that the entanglement cost equals the regularized entanglement of formation for any infinite-dimensional quantum state $\rho_{AB}$ with finite quantum entropy on at least one of the subsystems $A$ or $B$. This generalizes a…

Quantum Physics · Physics 2026-05-26 Hayata Yamasaki , Kohdai Kuroiwa , Patrick Hayden , Ludovico Lami

In this work, we construct small sets of bipartite orthogonal pure states that cannot be perfectly distinguished by local operations and classical communication (LOCC). We mention that not all the states within the constructed sets are…

Quantum Physics · Physics 2026-03-31 Saronath Halder , Suchetana Goswami

Using the convex-roof extended negativity and the negativity of assistance as quantifications of bipartite entanglement, we consider the possible remotely-distributed entanglement. For two pure states $\ket{\phi}_{AB}$ and $\ket{\psi}_{CD}$…

Quantum Physics · Physics 2015-05-18 Jeong San Kim , Soojoon Lee

Much of the theory of entanglement concerns the transformations that are possible to a state under local operations with classical communication (LOCC); however, this set of operations is complicated and difficult to describe…

Quantum Physics · Physics 2008-08-24 Ognyan Oreshkov , Todd A. Brun

We show how to simplify the computation of the entanglement of formation and the relative entropy of entanglement for states, which are invariant under a group of local symmetries. For several examples of groups we characterize the state…

Quantum Physics · Physics 2009-11-06 K. G. H. Vollbrecht , R. F. Werner

I consider deterministic distinguishability of a set of orthogonal, bipartite states when only a single copy is available and the parties are restricted to local operations and classical communication, but with the additional requirement…

Quantum Physics · Physics 2009-11-13 Scott M. Cohen

In general the calculation of robustness of entanglement for the mixed entangled quantum states is rather difficult to handle analytically. Using the the convex semi-definite programming method, the robustness of entanglement of some mixed…

Quantum Physics · Physics 2016-09-08 M. A. Jafarizadeh , M. Mirzaee , M. Rezaee

We introduce and define a set of functions on pure bipartite states called entanglement moments. Usual entanglement measures tell you if two systems are entangled, while entanglement moments tell you both if and how two systems are…

Quantum Physics · Physics 2014-09-08 Justin H. Wilson , Joe Mitchell , Victor Galitski

A general description of entanglement is suggested as an action realized by an arbitrary operator over given disentangled states. The related entanglement measure is defined. Because of its generality, this definition can be employed for…

Quantum Physics · Physics 2009-11-10 V. I. Yukalov

We study the quantification of genuine multipartite entanglement (GME) for general multipartite states. A set of inequalities satisfied by the entanglement of $N$-partite pure states is derived by exploiting the restrictions on entanglement…

Quantum Physics · Physics 2022-12-15 Zhi-Xiang Jin , Yuan-Hong Tao , Yao-Ting Gui , Shao-Ming Fei , Xianqing Li-Jost , Cong-Feng Qiao

The relative entropy of entanglement is defined in terms of the relative entropy between an entangled state and its closest separable state (CSS). Given a multipartite-state on the boundary of the set of separable states, we find a closed…

Quantum Physics · Physics 2011-06-03 Shmuel Friedland , Gilad Gour

We show that the two notions of entanglement: the maximum of the geometric measure of entanglement and the maximum of the nuclear norm is attained for the same states. We affirm the conjecture of Higuchi-Sudberry on the maximum entangled…

Quantum Physics · Physics 2017-05-23 Harm Derksen , Shmuel Friedland , Lek-Heng Lim , Li Wang