English

Dynamics of quantum entanglement

Quantum Physics 2009-11-06 v3

Abstract

A model of discrete dynamics of entanglement of bipartite quantum state is considered. It involves a global unitary dynamics of the system and periodic actions of local bistochastic or decaying channel. For initially pure states the decay of entanglement is accompanied with an increase of von Neumann entropy of the system. We observe and discuss revivals of entanglement due to unitary interaction of both subsystems. For some mixed states having different marginal entropies of both subsystems (one of them larger than the global entropy and the other one one smaller) we find an asymmetry in speed of entanglement decay. The entanglement of these states decreases faster, if the depolarizing channel acts on the "classical" subsystem, characterized by smaller marginal entropy.

Keywords

Cite

@article{arxiv.quant-ph/0008115,
  title  = {Dynamics of quantum entanglement},
  author = {Karol Zyczkowski and Pawel Horodecki and Michal Horodecki and Ryszard Horodecki},
  journal= {arXiv preprint arXiv:quant-ph/0008115},
  year   = {2009}
}

Comments

10 pages, Revtex, 10 figures, refined version