2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124312We present an improved protocol for entanglement purification of bipartite mixed states. The protocol requires two-way classical communication and hence implies an improved lower bound on the quantum capacity with two-way classical communication of the quantum depolarizing channel.10 pages with 4 figures, references addedQuantum Physicstext