English
Related papers

Related papers: A matrix inequality related to the entanglement di…

200 papers

There is an ongoing effort to quantify entanglement of quantum pure states for systems with more than two subsystems. We consider three approaches to this problem for three-qubit states: choosing a basis which puts the state into a standard…

Quantum Physics · Physics 2009-11-06 Todd A. Brun , Oliver Cohen

We propose an entanglement distillation and purification scheme for symmetric two-mode entangled Gaussian states that allows to asymptotically extract a pure entangled Gaussian state from any input entangled symmetric Gaussian state. The…

Quantum Physics · Physics 2015-05-20 Jaromir Fiurasek

Computing the exact rate at which entanglement can be distilled from noisy quantum states is one of the longest-standing questions in quantum information. We give an exact solution for entanglement distillation under the set of dually…

Quantum Physics · Physics 2024-11-25 Ludovico Lami , Bartosz Regula

A concern has been expressed that ``the Jaynes principle can produce fake entanglement'' [R. Horodecki et al., Phys. Rev. A {\bf 59}, 1799 (1999)]. In this paper we discuss the general problem of distilling maximally entangled states from…

Quantum Physics · Physics 2009-11-06 Todd A. Brun , Carlton M. Caves , Ruediger Schack

We exhibit a two-parameter family of bipartite mixed states $\rho_{bc}$, in a $d\otimes d$ Hilbert space, which are negative under partial transposition (NPT), but for which we conjecture that no maximally entangled pure states in $2\otimes…

We present a way for the entanglement distillation of genuine mixed state. Different from the conventional mixed state in entanglement purification protocol, each components of the mixed state in our protocol is a less-entangled state,…

Quantum Physics · Physics 2014-04-15 Yu-Bo Sheng , Lan Zhou

We experimentally generate and tomographically characterize a mixed, genuinely non-Gaussian bipartite continuous-variable entangled state. By testing entanglement in 2$\times$2-dimensional two-qubit subspaces, entangled qubits are localized…

Quantum Physics · Physics 2015-03-17 T. Kiesel , W. Vogel , B. Hage , R. Schnabel

Distillation of entanglement using only Gaussian operations is an important primitive in quantum communication, quantum repeater architectures, and distributed quantum computing. Existing distillation protocols for continuous degrees of…

Quantum Physics · Physics 2013-05-30 Earl T. Campbell , Jens Eisert

Quantum mechanics is already 100 years old, but remains alive and full of challenging open problems. On one hand, the problems encountered at the frontiers of modern theoretical physics like Quantum Gravity, String Theories, etc. concern…

Quantum Physics · Physics 2016-09-21 M. Lewenstein , D. Bruss , J. I. Cirac , B. Kraus , M. Kus , J. Samsonowicz , A. Sanpera , R. Tarrach

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

Uncontrolled interactions with the environment introduce errors that remain a significant challenge to the reliability of quantum technologies using entanglement. An essential method to overcome or mitigate these errors is entanglement…

Quantum Physics · Physics 2025-08-05 Christopher Popp , Tobias C. Sutter , Beatrix C. Hiesmayr

The potential impact of future quantum networks hinges on high-quality quantum entanglement shared between network nodes. Unavoidable real-world imperfections necessitate means to improve remote entanglement by local quantum operations.…

We present a detailed theoretical analysis for the distillation of one copy of a mixed two-mode continuous-variable entangled state using beamsplitters and coherent photon-detection techniques, including conventional on-off detectors and…

Quantum Physics · Physics 2013-05-29 ShengLi Zhang , Peter van Loock

We obtain the necessary and sufficient separability and distillability conditions of mixtures of a maximally entangled state and the completely separable state in relativistic setting. In an inertial frame we study the entanglement under…

Quantum Physics · Physics 2012-01-10 Shahpoor Moradi

We discuss a specific entanglement distillation scheme under the constraint of finite samples of entangled qubit pairs. It is shown that an iterative process can be explicitly formulated. The average fidelity of this process can be enhanced…

Quantum Physics · Physics 2007-05-23 Stefan Probst-Schendzielorz , Thorsten Bschorr , Matthias Freyberger

The degradation of entanglement in quantum memories due to decoherence is a critical challenge for scalable quantum networks. We present an entanglement distillation protocol based on the [[4,2,2]] quantum error-detecting code, deriving…

Quantum Physics · Physics 2025-09-09 Huidan Zheng , Gunsik Min , Ilkwon Sohn , Jun Heo

Entanglement distillation is a procedure for extracting from one or more pairs of entangled qubits a smaller number of pairs with a higher degree of entanglement that is essential for many applications in quantum information science.…

Quantum Physics · Physics 2008-08-26 Taehyun Kim , Franco N. C. Wong

The distribution of entangled states between distant parties in an optical network is crucial for the successful implementation of various quantum communication protocols such as quantum cryptography, teleportation and dense coding [1-3].…

We present a practical entanglement distillation protocol (EDP) with linear optics for a genuine mixed state. Each components of the genuine mixed state is a pure less-entangled state. After successfully performing this EDP, we can obtain a…

Quantum Physics · Physics 2014-01-16 Yu-Bo Sheng , Lan Zhou , Xing-Fu Wang

There has been a surge of progress in recent years in developing algorithms for testing and learning quantum states that achieve optimal copy complexity. Unfortunately, they require the use of entangled measurements across many copies of…

Quantum Physics · Physics 2020-04-20 Sebastien Bubeck , Sitan Chen , Jerry Li