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Related papers: Limits for entanglement measures

200 papers

We consider entanglement distillation under the assumption that the input states are allowed to be correlated among each other. We hence replace the usually considered independent and identically-distributed hypothesis by the weaker…

Quantum Physics · Physics 2013-08-27 Fernando G. S. L. Brandao , Jens Eisert

We explore and develop the mathematics of the theory of entanglement measures. After a careful review and analysis of definitions, of preliminary results, and of connections between conditions on entanglement measures, we prove a sharpened…

Quantum Physics · Physics 2015-06-26 Matthew J. Donald , Michal Horodecki , Oliver Rudolph

In a closed system, the total number of particles is fixed. We ask how much does this conservation law restrict the amount of entanglement that can be created. We derive a tight upper bound on the bipartite entanglement entropy in closed…

Quantum Physics · Physics 2020-02-18 Dana Faiez , Dominik Šafránek

Quantum entanglement is a useful resource for implementing communication tasks. However, for the resource to be useful in practice, it needs to be accessible by parties with bounded computational resources. Computational entanglement…

Quantum Physics · Physics 2025-09-29 Ilia Ryzov , Faedi Loulidi , David Elkouss

The idea of signal amplification is ubiquitous in the control of physical systems, and the ultimate performance limit of amplifiers is set by quantum physics. Increasing the amplitude of an unknown quantum optical field, or more generally…

Quantum Physics · Physics 2010-06-16 G. Y. Xiang , T. C. Ralph , A. P. Lund , N. Walk , G. J. Pryde

Equilibrium states of infinite extended lattice systems at high temperature are studied with respect to their entanglement. Two notions of separability are offered. They coincide for finite systems but differ for infinitely extended ones.…

Quantum Physics · Physics 2009-11-10 H. Narnhofer

A common view in monitored quantum dynamics is that local measurements suppress entanglement growth. We show that this intuition can fail in a one-dimensional spinful fermionic chain governed by a BCS Hamiltonian with pairing strength…

Quantum Physics · Physics 2026-04-07 Rui-Jing Guo , Ji-Yao Chen , Zhi-Yuan Wei

The notion of distillable entanglement is one of the fundamental concepts of quantum information theory. Unfortunately, there is an apparent mismatch between the intuitive and rigorous definitions of distillable entanglement. To be precise,…

Quantum Physics · Physics 2009-10-31 Eric M. Rains

Bound entangled states are states that are entangled but from which no entanglement can be distilled if all parties are allowed only local operations and classical communication. However, in creating these states one needs nonzero…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Joseph B. Altepeter , Paul M. Goldbart , William J. Munro

Coherent enhancement is a powerful mechanism for improving the sensitivity of a wide range of detectors, but its practical use is often limited by the difficulty of preparing the required quantum states. We show that this difficulty has a…

High Energy Physics - Phenomenology · Physics 2026-05-12 Zachary Bogorad , Roni Harnik

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

Entanglement of formation quantifies the entanglement of a state in terms of the entropy of entanglement of the least entangled pure state needed to prepare it. An analytical expression for this measure exists only for special cases, and…

Quantum Physics · Physics 2019-05-29 Spyros Tserkis , Sho Onoe , Timothy C. Ralph

A measure of entanglement production by quantum operations is suggested. This measure is general, being valid for operations over pure states as well as over mixed states, for equilibrium as well as for nonequilibrium processes. The measure…

Quantum Physics · Physics 2025-08-01 V. I. Yukalov , E. P. Yukalova

We show that the entanglement of cost and entanglement of distillation can be vague when we consider a more general form of entanglement manipulation in which we collectively deal with not only states of our concern but also other states.…

Quantum Physics · Physics 2009-11-07 W. -Y. Hwang , K. Matsumoto

We show that the process of entanglement distillation is irreversible by showing that the entanglement cost of a bound entangled state is finite. Such irreversibility remains even if extra pure entanglement is loaned to assist the…

Quantum Physics · Physics 2009-11-07 G. Vidal , J. I. Cirac

Entanglement distillation is an indispensable ingredient in extended quantum communication networks. Distillation protocols are necessarily non-deterministic and require advanced experimental techniques such as noiseless amplification.…

The notion of entanglement fidelity is to measure entanglement preservation through quantum channels. Nevertheless, the amount of entanglement present in a state of a quantum system at any time is measured by quantities known as measures of…

Quantum Physics · Physics 2020-04-07 Vahid Azimi Mousolou

Entanglement [1, 2] enables powerful new quantum technologies [3-8], but in real-world implementations, entangled states are often subject to decoherence and preparation errors. Entanglement distillation [9, 10] can often counteract these…

Quantum Physics · Physics 2010-09-24 Jonathan Lavoie , Rainer Kaltenbaek , Marco Piani , Kevin J. Resch

We demonstrate that the entropy of entanglement and the distillable entanglement of regions with respect to the rest of a general harmonic lattice system in the ground or a thermal state scale at most as the boundary area of the region.…

Quantum Physics · Physics 2009-11-11 M. Cramer , J. Eisert , M. B. Plenio , J. Dreissig

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