A Teleportation with Two Quantum Channels

Recently a quantum teleportation scheme has been analyzed by Wangner et al. (J. Opt. Soc. Am. B 27:A73–A80, 2010 ) which is based on spatially and temporarily resolved collective spontaneous emission. We study a similar model, which has the two atoms trapped in a resonant cavity instead of in the free vacuum space. It is found that the quantum channel experiences entanglement of sudden death (ESD), yet every time this channel can recover after an interval of time. Surprisingly, we demonstrate there exits another channel to assist the initial channel to complete the teleportation, and the fidelity can be well beyond the classical limit of 2/3, with the increase of dipole-dipole interaction.