MiS Preprint Repository

We have decided to discontinue the publication of preprints on our preprint server as of 1 March 2024. The publication culture within mathematics has changed so much due to the rise of repositories such as ArXiV ( that we are encouraging all institute members to make their preprints available there. An institute's repository in its previous form is, therefore, unnecessary. The preprints published to date will remain available here, but we will not add any new preprints here.

MiS Preprint

Concurrence, Tangle and Fully Entangled Fraction of Quantum Entanglement

Ming Li, Shao-Ming Fei and Xianqing Li-Jost


We show that although we can not distill a singlet from many pairs of bound entangled states, the concurrence and tangle of two entangled quantum states are always strictly larger than that of one, even both entangled quantum states are bound entangled. We present a relation between the concurrence and the fidelity of optimal teleportation. We also give new upper and lower bounds for concurrence and tangle.

Concurrence, entanglement, Teleportation

Related publications

2010 Repository Open Access
Ming Li, Shao-Ming Fei and Xianqing Li-Jost

Concurrence, tangle and fully entangled fraction

In: Chinese physics / B, 19 (2010) 9, p. 090315