English

Quantifying quantum discord and entanglement of formation via unified purifications

Quantum Physics 2015-05-19 v2

Abstract

We propose a scheme to evaluate the amount of quantum discord and entanglement of formation for mixed states, and reveal their ordering relation via an intrinsic relationship between the two quantities distributed in different partners of the associated purification. This approach enables us to achieve analytical expressions of the two measures for a sort of quantum states, such as an arbitrary two-qubit density matrix reduced from pure three-qubit states and a class of rank-2 mixed states of 4\times 2 systems. Moreover, we apply the scheme to characterize fully the dynamical behavior of quantum correlations for the specified physical systems under decoherence.

Keywords

Cite

@article{arxiv.1006.4727,
  title  = {Quantifying quantum discord and entanglement of formation via unified purifications},
  author = {Li-Xiang Cen and Xin-Qi Li and JiuShu Shao and YiJing Yan},
  journal= {arXiv preprint arXiv:1006.4727},
  year   = {2015}
}

Comments

4 pages, 2 figures, accepted for publication in Phys. Rev. A