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Related papers: Maximally entangled mixed states made easy

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We present a one-shot method for preparing pure entangled states between a sender and a receiver at a minimal cost of entanglement and quantum communication. In the case of preparing unentangled states, an earlier paper showed that a…

Quantum Physics · Physics 2007-05-23 Anura Abeyesinghe , Patrick Hayden , Graeme Smith , Andreas Winter

We show that {\it one} single-mode squeezed state distributed among $N$ parties using linear optics suffices to produce a truly $N$-partite entangled state for any nonzero squeezing and arbitrarily many parties. From this $N$-partite…

Quantum Physics · Physics 2009-10-31 P. van Loock , Samuel L. Braunstein

We propose a scheme to unconditionally entangle the internal states of atoms trapped in separate high finesse optical cavities. The scheme uses the technique of quantum reservoir engineering in a cascaded cavity QED setting, and for ideal…

Quantum Physics · Physics 2009-11-10 Stephen Clark , Amy Peng , Mile Gu , Scott Parkins

Known entanglement purification protocols for mixed states use collective measurements on several copies of the state in order to increase the entanglement of some of them. We address the question of whether it is possible to purify the…

Quantum Physics · Physics 2009-10-31 N. Linden , S. Massar , S. Popescu

Our study employs a connected correlation matrix to quantify Quantum Entanglement. The matrix encompasses all necessary measures for assessing the degree of entanglement between particles. We begin with a three-qubit state and involve…

Quantum Physics · Physics 2023-12-06 Xingyu Guo , Chen-Te Ma

We experimentally demonstrate optimal entanglement distillation from two forms of two-qubit mixed states under local filtering operations according to the constructive method intruduced by F. Verstraete et al. [Phys. Rev. A 64, 010101(R)…

Quantum Physics · Physics 2007-05-23 Zhi-Wei Wang , Xiang-Fa Zhou , Yun-Feng Huang , Yong-Sheng Zhang , Xi-Feng Ren , Guang-Can Guo

The maximum entanglement between two coupled qubits in the steady state under two independent incoherent sources of excitation is reported. Asymmetric configurations where one qubit is excited while the other one dissipates the excitation…

Quantum Physics · Physics 2011-01-11 Elena del Valle

We investigate multiple linear optical teleportation in the Knill-Laflamme-Milburn scheme with both maximally and nonmaximally entangled states. We show that if the qubit is teleported several times via nonmaximally entangled state then the…

Quantum Physics · Physics 2008-07-24 Joanna Modlawska , Andrzej Grudka

A fully connected quantum network with a wavelength division multiplexing architecture plays an increasingly pivotal role in quantum information technology. With such architecture, an entanglement-based network has been demonstrated in…

We report an experiment to generate maximally entangled states of D-dimensional quantum systems, qudits, by using transverse spatial correlations of two parametric down-converted photons. Apertures with D-slits in the arms of the twin…

Quantum Physics · Physics 2009-11-10 Leonardo Neves , G. Lima , J. G. Aguirre Gómez , C. H. Monken , C. Saavedra , S. Pádua

In some off-resonant cases, the reduced density matrix of two atoms symmetrically coupled with an optical cavity can very approximately approach to maximally entangled mixed states or maximal Bell violation mixed states in their evolution.…

Quantum Physics · Physics 2015-06-26 Shang-Bin Li , Jing-Bo Xu

We discuss the problem of characterizing upper bounds on entanglement in a bipartite quantum system when only the reduced density matrices (marginals) are known. In particular, starting from the known two-qubit case, we propose a family of…

We investigate the entanglement properties of pure quantum states describing $n$ qubits. We characterize all multipartite states which can be maximally entangled to local auxiliary systems using controlled operations. A state has this…

Quantum Physics · Physics 2013-05-29 C. Kruszynska , B. Kraus

Heterogeneous bipartite quantum pure states, composed of two subsystems with a different number of levels, cannot have both reductions maximally mixed. In this work, we demonstrate existence of a wide range of highly entangled states of…

Quantum Physics · Physics 2016-08-06 D. Goyeneche , J. Bielawski , K. Życzkowski

Entanglement can be considered as a special quantum correlation, but not the only kind. Even for a separable quantum system, it is allowed to exist non-classical correlations. Here we propose two dissipative schemes for generating a…

Quantum Physics · Physics 2020-01-22 X. X. Li , H. D. Yin , D. X. Li , X. Q. Shao

We study the conditions when mixtures of entangled pure states with maximally mixed one-qudit reduced density matrices remain entangled. We found that the resulting mixed state remains entangled when the number of entangled pure states to…

Quantum Physics · Physics 2016-06-10 Marvin M. Flores , Eric A. Galapon

The concept of entanglement splitting is introduced by asking whether it is possible for a party possessing half of a pure bipartite quantum state to transfer some of his entanglement with the other party to a third party. We describe the…

Quantum Physics · Physics 2009-10-31 Dagmar Bruss

Quantum teleportation of qudits is revisited. In particular, we analyze the case where the quantum channel corresponds to a non-maximally entangled state and show that the success of the protocol is directly related to the problem of…

Quantum Physics · Physics 2009-11-10 L. Roa , A. Delgado , I. Fuentes-Guridi

Contrary to A.Borras et al.'s [1] conjecture, a genuine maximally seven-qubit entangled state is presented. We find a seven-qubit state whose marginal density matrices for subsystems of 1,2- qubits are all completely mixed and for…

Quantum Physics · Physics 2015-05-30 Xin-Wei Zha , Hai-Yang Song , Jian-Xia Qi , Dong Wang , Qian Lan

We find a coupling-strength configuration for a linear chain of N spins which gives rise to simultaneous multiple Bell states. We suggest a way such an interesting entanglement pattern can be used in order to distribute maximally entangled…

Quantum Physics · Physics 2008-03-02 C. Di Franco , M. Paternostro , M. S. Kim