In this paper we present the novel qualities of entanglement of formation (EoF) for general (so also infinite-dimensional) quantum systems. A major benefit of our presentation is a rigorous description of EoF. In particular, we indicate how this description may be used to examine optimal decompositions. Illustrative examples showing the method of estimation of EoF are given.

Journal of Physics A Mathematical and GeneralDec 21, 200117 citations

Physics Letters A

Entanglement of formation for one-dimensional magnetic systems with defects

Zhen Huang, Omar Osenda, Sabre Kais

Published Jan 23, 2004• 32 citations

Publisher

DOI: 10.1016/j.physleta.2004.01.022

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L

spins with the rest of the system is also estimated which is found to increase logarithmically with

L

. The dependence on the quench time puts a constraint on the block size

L

. It is also pointed out that the Lipkin-Meshkov-Glick model in point-splitting regularized form appears as a combination of the

\mathit{XXX}

model and Ising model with magnetic field in the negative

z

axis. This unveils the underlying conformal symmetry at criticality which is lost in the sharp point limit. Our analysis shows that the density of defects as well as the scaling behavior of the entanglement entropy follows a universal behavior in all these systems.