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We propose an entanglement purification protocol for high-dimensional multipartite systems. In the protocol we can select a subensemble in a pure generalized Greenberger-Horne-Zeilinger (GHZ) state. This post-selection can be made by…

Quantum Physics · Physics 2011-11-09 Yong Wook Cheong , Seung-Woo Lee , Jinhyoung Lee , Hai-Woong Lee

We introduce a simple, experimentally realisable, entanglement manipulation protocol for exploring mixed state entanglement. We show that for both non-maximally entangled pure, and mixed polarisation-entangled two qubit states, an increase…

Quantum Physics · Physics 2009-11-06 R. T. Thew , W. J. Munro

In [J. C. Howell and J. A. Yeazell, Phys. Rev. A 62, 012102 (2000)], a proposal is made to generate entangled macroscopically distinguishable states of two spatially separated traveling optical modes. We model the decoherence due to light…

Quantum Physics · Physics 2016-04-26 J. Clausen , L. Knoell , D. -G. Welsch

Entanglement distillation, a fundamental building block of quantum networks, enables the purification of noisy entangled states shared among distant nodes by local operations and classical communication. Its practical realization presents…

Quantum Physics · Physics 2026-05-27 Jaemin Kim , Karthik Mohan , Sung Won Yun , Joonwoo Bae

We study the problem of general entanglement purification protocols. Suppose Alice and Bob share a bipartite state $\rho$ which is ``reasonably close'' to perfect EPR pairs. The only information Alice and Bob possess is a lower bound on the…

Quantum Physics · Physics 2007-05-23 Andris Ambainis , Ke Yang

An iterative random procedure is considered allowing an entanglement purification of a class of multi-mode quantum states. In certain cases, a complete purification may be achieved using only a single signal state preparation. A physical…

Quantum Physics · Physics 2009-11-10 J Clausen , L Knoell , D-G Welsch

Multipartite entanglement has a much more complex structure than bipartite entanglement. A state that lacks generic multipartite entanglement is 2-producible, i.e. it can be written as a tensor product of at most 2-partite entangled states.…

Quantum Physics · Physics 2026-04-09 Tian-Ren Jin , Yu-Ran Zhang , Heng Fan

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

The efficient generation of high-fidelity entangled states is the key element for long-distance quantum communication, quantum computation and other quantum technologies, and at the same time the most resource-consuming part in many…

Quantum Physics · Physics 2021-07-28 Ferran Riera Sàbat , Pavel Sekatski , Alexander Pirker , Wolfgang Dür

Linden, Massar and Popescu have recently given an optimization argument to show that a single two-qubit Werner state, or any other mixture of the maximally entangled Bell states, cannot be purified by local operations and classical…

Quantum Physics · Physics 2009-10-31 Adrian Kent

We present an improved protocol for entanglement purification of bipartite mixed states using several states at a time rather than two at a time as in the traditional recurrence method. We also present a generalization of the hashing method…

Quantum Physics · Physics 2007-05-23 Elitza N. Maneva , John A. Smolin

We present multiparty entanglement purification protocols that are capable of purifying arbitrary graph states directly. We develop recurrence and breeding protocols and compare our methods with strategies based on bipartite entanglement…

Quantum Physics · Physics 2007-05-23 Caroline Kruszynska , Akimasa Miyake , Hans J. Briegel , Wolfgang Dür

We prove that all purifications of a non-factorable state (i.e., the state which cannot be expressed in a form $\rho_{AB}=\rho_A\otimes\rho_B$) are entangled. We also show that for any bipartite state there exists a pair of measurements…

Quantum Physics · Physics 2009-11-07 Jan Bouda , Vladimir Buzek

We propose a scheme for optimal Gaussian purification of coherent states from several imperfect copies. The proposal is experimentally demonstrated for the case of two copies of a coherent state sent through independent noisy channels. Our…

Quantum Physics · Physics 2009-11-11 Ulrik L. Andersen , Radim Filip , Jaromir Fiurasek , Vincent Josse , Gerd Leuchs

We investigate multiparticle entanglement purification schemes which allow one to purify all two colorable graph states, a class of states which includes e.g. cluster states, GHZ states and codewords of various error correction codes. The…

Quantum Physics · Physics 2016-08-16 H. Aschauer , W. Dür , H. -J. Briegel

Purification is a tool that allows to represent mixed quantum states as pure states on enlarged Hilbert spaces. A purification of a given state is not unique and its entanglement strongly depends on the particular choice made. Moreover, in…

Strongly Correlated Electrons · Physics 2019-01-08 Johannes Hauschild , Eyal Leviatan , Jens H. Bardarson , Ehud Altman , Michael P. Zaletel , Frank Pollmann

Purification is a powerful technique in quantum physics whereby a mixed quantum state is extended to a pure state on a larger system. This process is not unique, and in systems composed of many degrees of freedom, one natural purification…

High Energy Physics - Theory · Physics 2018-02-14 Phuc Nguyen , Trithep Devakul , Matthew G. Halbasch , Michael P. Zaletel , Brian Swingle

The distribution of entangled states between distant locations will be essential for the future large scale realization of quantum communication schemes such as quantum cryptography and quantum teleportation. Because of the unavoidable…

Quantum Physics · Physics 2016-09-08 Jian-Wei Pan , Christoph Simon , Caslav Brukner , Anton Zeilinger

Given multiple copies of a mixed quantum state with an unknown, nondegenerate principal eigenspace, quantum state purification is the task of recovering a quantum state that is closer to the principal eigenstate. A streaming protocol…

Quantum Physics · Physics 2025-03-31 Daniel Grier , Debbie Leung , Zhi Li , Hakop Pashayan , Luke Schaeffer

Entanglement plays an indispensable role in numerous quantum information and quantum computation tasks, underscoring the need for efficiently verifying entangled states. In recent years, quantum state verification has received increasing…

Quantum Physics · Physics 2025-12-15 Lan Zhang , Yinfei Li , Ye-Chao Liu , Jiangwei Shang