Entanglement Purification for Quantum Repeater
Zhen Zhu Zhou, Wei He, Chun Dan Zhu, Ying Wang · Advanced materials research · 2013
We study various kinds of entanglement purification schemes for quantum repeater distributed maximally entangled pairs over long distances. We then investigate two protocols in detail, and present that they have the same essence in principle but operated by different means. In order to compare the two different protocols, we introduce a parameter represented the admixture degree of system to show the optimal protocol that is obtainable. Finally, we present that the efficiency of purification protocol relate to the fidelity of the initial states of the system. For the initial state of the system with high fidelity entanglement, we can obtain the required particles after a few iterations.