Bouwmeester et al. reply — Braunstein and Kimble observe correctly that, in the Innsbruck experiment, one does not always observe a teleported photon conditioned on a coincidence recording at the Bell-state analyser. In their opinion, this affects the fidelity of the experiment, but we believe, in contrast, that it has no significance, and that when a teleported photon appears, it has all the properties required by the teleportation protocol. These properties can never be achieved by "abandoning teleportation altogether and transmitting randomly selected polarization states" as Braunstein and Kimble suggest. The fact that there will be events where no teleported photons are created merely affects the efficiency of the experiment. This suggests that the measure of fidelity used by Braunstein and Kimble is unsuitable for our experiment.

1. Institut für Experimentalphysik, Universität, Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria