  Quantum teleportation -- the transmission and reconstruction over arbitrary
distances of the state of a quantum system -- is demonstrated experimentally.
During teleportation, an initial photon which carries the polarization that is
to be transferred and one of a pair of entangled photons are subjected to a
measurement such that the second photon of the entangled pair acquires the
polarization of the initial photon. This latter photon can be arbitrarily far
away from the initial one. Quantum teleportation will be a critical ingredient
for quantum computation networks.
