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October 2006 Volume 2 No 10

Quantum teleportation describes the transfer of a quantum state from one place to another, by a sender who knows neither the state to be teleported nor the location of the receiver. The phenomenon is one of the most intriguing examples of how quantum entanglement can assist in realizing practical tasks, and is involved in numerous quantum communication and quantum computation schemes. Quantum teleportation of single bits of quantum information has been demonstrated before, but large-scale applications require the transfer of composite systems. Now Qiang Zhang and colleagues report the teleportation of combined polarization states — including entanglement — of two photons, the key to their success being the development of an efficient six-photon interferometer.

Letter by Zhang et al | News and Views by Walther