English
Related papers

Related papers: An improved bound on distillable entanglement

200 papers

A remarkable feature of typical ground states of strongly-correlated many-body systems is that the entanglement entropy is not an extensive quantity. In one dimension, there exists a proof that a finite correlation length sets a constant…

Quantum Physics · Physics 2018-07-13 Jaeyoon Cho

We investigate how to enhance entanglement in the steady state of interacting two-level systems. The steady state is reached by spontaneous decay of the individual systems. When we additionally couple them to a dissipative two-level ancilla…

Quantum Physics · Physics 2015-12-09 Joachim Fischbach , Matthias Freyberger

We consider Dirichlet Laplacians on straight strips in R^2 or layers in R^3 with a weak local deformation. First we generalize a result of Bulla et al. to the three-dimensional situation showing that weakly coupled bound states exist if the…

Mathematical Physics · Physics 2020-01-20 D. Borisov , P. Exner , R. Gadylshin , D. Krejcirik

It has been known for some years that entanglement entropy obtained from partial trace does not provide the correct entanglement measure when applied to systems of identical particles. Several criteria have been proposed that have the…

High Energy Physics - Theory · Physics 2013-03-05 A. P. Balachandran , T. R. Govindarajan , Amilcar R. de Queiroz , A. F. Reyes-Lega

In the quest of completely describing entanglement in the general case of a finite number of parties sharing a physical system of finite dimensional Hilbert space a new entanglement magnitude is introduced for its pure and mixed states:…

Quantum Physics · Physics 2009-10-31 Guifre Vidal , Rolf Tarrach

Entanglement measures constructed from two positive, but not completely positive maps on density operators are used as constraints in placing bounds on the entanglement of formation, the tangle, and the concurrence of 4 x N mixed states.…

Quantum Physics · Physics 2007-07-02 Animesh Datta , Steven T. Flammia , Anil Shaji , Carlton M. Caves

An entangled quantum state is considered by applying a local photon excitation to each mode of an entangled coherent state. The entanglement property is investigated in terms of the entropy of entanglement. It is shown that applying a…

Quantum Physics · Physics 2023-04-13 Arpita Chatterjee

The bounds on concurrence of the superposition state in terms of those of the states being superposed are studied in this paper. The bounds on concurrence are quite different from those on the entanglement measure based on von Neumann…

Quantum Physics · Physics 2009-11-13 Chang-shui Yu , X. X. Yi , He-shan Song

Based on the form invariance of the structures given by Khinchin's axiomatic foundations of information theory and the pseudoadditivity of the Tsallis entropy indexed by q, the concept of conditional entropy is generalized to the case of…

Quantum Physics · Physics 2009-11-06 Sumiyoshi Abe , A. K. Rajagopal

We analyze the existence of activable bound entangled states in multi-particle systems. We first give a series of examples which illustrate some different ways in which bound entangled states can be activated by letting some of the parties…

Quantum Physics · Physics 2009-11-06 W. Dür , J. I. Cirac

Recent work has argued that the concepts of entanglement and nonlocality must be taken seriously even in systems consisting of only a single particle. These treatments, however, are nonrelativistic and, if single particle entanglement is…

Quantum Physics · Physics 2015-05-13 Jacob Dunningham , Vlatko Vedral

We derive lower bounds for the attainable fidelity of standard entanglement purification protocols when local operations and measurements are subjected to errors. We introduce an error parameter which measures the distance between the ideal…

Quantum Physics · Physics 2009-10-31 G. Giedke , H. Briegel , J. I. Cirac , P. Zoller

It is well known that for pure states the relative entropy of entanglement is equal to the reduced entropy, and the closest separable state is explicitly known as well. The same holds for Renyi relative entropy per recent results. We ask…

Quantum Physics · Physics 2021-02-10 Anna Vershynina

In this paper, we are concerned with the validity of Prandtl boundary layer expansion for the solutions to two dimensional (2D) steady viscous incompressible magnetohydrodynamics (MHD) equations in a domain $\{(X, Y)\in[0,…

Analysis of PDEs · Mathematics 2020-01-20 Shijin Ding , Zhilin Lin , Feng Xie

Entanglement R\'enyi-$\alpha$ entropy is an entanglement measure. It generalizes the entanglement of formation, and they coincide when $\alpha$ tends to 1. We derive analytical lower and upper bounds for the entanglement R\'enyi-$\alpha$…

Quantum Physics · Physics 2017-03-07 Wei Song , Lin Chen , Zhuo-Liang Cao

We characterize the set of shared quantum states which contain a cryptographically private key. This allows us to recast the theory of privacy as a paradigm closely related to that used in entanglement manipulation. It is shown that one can…

Quantum Physics · Physics 2009-11-10 Karol Horodecki , Michal Horodecki , Pawel Horodecki , Jonathan Oppenheim

We investigate the entanglement and non-locality between specific spectral components of continuous variable two-mode squeezed mixed states, identifying their limits. These spectral components are selected from output modes using filters…

Quantum Physics · Physics 2025-04-23 Souvik Agasti

We show that the entanglement witnesses based on local orthogonal observables which are introduced in [S. Yu and N.-L. Liu, Phys. Rev. Lett. 95, 150504 (2005)] and [O. G\"uhne, M. Mechler, G. T\'oth and P. Adam, Phys. Rev. A 74, 010301…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yong-Sheng Zhang , Shun Zhang , Guang-Can Guo

A convergent iterative procedure is proposed for the calculation of the relative entropy of entanglement of a given bipartite quantum state. When this state turns out to be non-separable the algorithm provides the corresponding optimal…

Quantum Physics · Physics 2009-11-07 Jaroslav Rehacek , Zdenek Hradil

We define nonlocal predictability as how well one observer can predict another's measurement outcomes without classical communication, given full knowledge of the shared quantum state and measurement settings. The local bound on nonlocal…

Quantum Physics · Physics 2026-02-19 Chirag Srivastava , Aparajita Bhattacharyya , Ujjwal Sen