Transfer of quantum states using finite resources - art. no. 042305

We discuss the problem of transfering a qubit from Alice to Bob using a noi sy quantum channel and only finite resources. As the basic protocol for the transfer we apply quantum teleportation. It turns out that, for a certain quality of the channel, direct teleportation combined with qubit purificati on is superior to entanglement purification of the channel. If, however, th e quality of the channel is rather low, one should simply apply an estimati on-preparation scheme.