English
Related papers

Related papers: Optimal Interpolation of Entanglement Purification…

200 papers

We characterize the multipartite entanglement of a system of n qubits in terms of the distribution function of the bipartite purity over all balanced bipartitions. We search for those (maximally multipartite entangled) states whose purity…

Quantum Physics · Physics 2010-02-01 Paolo Facchi , Giuseppe Florio , Ugo Marzolino , Giorgio Parisi , Saverio Pascazio

We construct new entanglement distillation protocols by interpolating between the recurrence and hashing protocols. This leads to asymptotic two-way distillation protocols, resulting in an improvement of the distillation rate for all mixed…

Quantum Physics · Physics 2009-11-10 Karl Gerd H. Vollbrecht , Frank Verstraete

We provide generalizations of known two-qubit entanglement distillation protocols for arbitrary Hilbert space dimensions. The protocols, which are analogues of the hashing and breeding procedures, are adapted to bipartite quantum states…

Quantum Physics · Physics 2009-11-07 K. G. H. Vollbrecht , M. M. Wolf

Entanglement purification is a powerful method to distill the high-quality entanglement from low-quality entanglement. In the paper, we propose an efficient two-step entanglement purification protocol (EPP) for the polarization entanglement…

Quantum Physics · Physics 2021-01-28 Lan Zhou , Yu-Bo Sheng

Since its discovery, the quantum entanglement becomes a promising resource in quantum communication and computation. However, the entanglement is fragile due to the presence of noise in quantum channels. Entanglement purification is a…

Quantum Physics · Physics 2023-04-26 Peishun Yan , Lan Zhou , Wei Zhong , Yubo Sheng

We introduce a class of multiparticle entanglement purification protocols that allow us to distill a large class of entangled states. These include cluster states, GHZ states and various error correction codes all of which belong to the…

Quantum Physics · Physics 2009-11-10 W. Dür , H. Aschauer , H. -J. Briegel

Sharing genuine multipartite entanglement by considering collective use of copies of biseparable states, which are entangled across all bipartitions but lack genuine multipartite entanglement at the single-copy level, plays a central role…

Quantum Physics · Physics 2026-01-26 Swati Choudhary , Ujjwal Sen , Saronath Halder

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

We consider the problem of optimising the achievable EPR-pair distribution rate between multiple source-destination pairs in a quantum internet, where the repeaters may perform a probabilistic bell-state measurement and we may impose a…

Quantum Physics · Physics 2021-11-02 Kaushik Chakraborty , David Elkouss , Bruno Rijsman , Stephanie Wehner

Entanglement distillation refers to the task of transforming a collection of weakly entangled pairs into fewer highly entangled ones. It is a core ingredient in quantum repeater protocols, needed to transmit entanglement over arbitrary…

Quantum Physics · Physics 2016-01-20 Stephan Waeldchen , Janina Gertis , Earl T. Campbell , Jens Eisert

Quantum entanglement is the key to quantum communications over considerable distances. The first step for entanglement distribution among quantum communication nodes is to generate link-level Einstein-Podolsky-Rosen (EPR) pairs between…

Quantum Physics · Physics 2023-10-30 Karim Elsayed , Wasiur R. KhudaBukhsh , Amr Rizk

A method is proposed to characterize and quantify multipartite entanglement in terms of the probability density function of bipartite entanglement over all possible balanced bipartitions of an ensemble of qubits. The method is tested on a…

Quantum Physics · Physics 2007-05-25 P. Facchi , G. Florio , S. Pascazio

Entanglement distillation, the process of converting weakly entangled states into maximally entangled ones using Local Operations and Classical Communication (LOCC), is pivotal for robust entanglement-assisted quantum information processing…

Quantum Physics · Physics 2025-12-17 Christopher Popp , Tobias C. Sutter , Beatrix C. Hiesmayr

In tasks, where multipartite entanglement plays a central role, state purification is, due to inevitable noise, a crucial part of the procedure. We consider a scenario exploiting the multipartite entanglement in a straightforward…

Quantum Physics · Physics 2011-06-17 Marcus Huber , Martin Plesch

We put forward a method for optimized distillation of partly entangled pairs of qubits into a smaller number of more entangled pairs by recurrent local unitary operations and projections. Optimized distillation is achieved by minimization…

Quantum Physics · Physics 2009-10-31 T. Opatrny , G. Kurizki

Fidelity estimation is essential for the quality control of entanglement distribution networks. Because measurements collapse quantum states, we consider a setup in which nodes randomly sample a subset of the entangled qubit pairs to…

Quantum Physics · Physics 2022-10-10 Liangzhong Ruan

We propose and investigate a method to optimize recurrence entanglement purification protocols. The approach is based on a numerical search in the whole set of SU(4) matrices with the aid of a quasi-Newton algorithm. Our method evaluates…

Quantum Physics · Physics 2024-04-17 Francesco Preti , Tommaso Calarco , Juan Mauricio Torres , József Zsolt Bernád

We present an efficient entanglement purification protocol with hyperentanglement in which additional spatial entanglement is utilized to purify the two-particle polarization-entangled state. The bit-flip error and phase-flip error can be…

Quantum Physics · Physics 2014-10-06 Xi-Han Li

Given a finite number $N$ of copies of a qubit state we compute the maximum fidelity that can be attained using joint-measurement protocols for estimating its purity. We prove that in the asymptotic $N\to\infty$ limit, separable-measurement…

Quantum Physics · Physics 2009-11-11 E. Bagan , M. A. Ballester , R. Munoz-Tapia , O. Romero-Isart

Local Operations enhancing the entanglement of bipartite quantum states are of great interest in quantum information processing. Subject of this paper are local selective operations acting on single copies of states. Such operations can…

Quantum Physics · Physics 2007-05-23 Juliane Strassner , Christopher Witte