title: Experimental quantum teleportation over a high-loss free-space channel.
abstract: We present a high-fidelity quantum teleportation experiment over a high-loss free-space channel between two laboratories. We teleported six states of three mutually unbiased bases and obtained an average state fidelity of 0.82(1), well beyond the classical limit of 2/3. With the obtained data, we tomographically reconstructed the process matrices of quantum teleportation. The free-space channel attenuation of 31 dB corresponds to the estimated attenuation regime for a down-link from a low-earth-orbit satellite to a ground station. We also discussed various important technical issues for future experiments, including the dark counts of single-photon detectors, coincidence-window width etc. Our experiment tested the limit of performing quantum teleportation with state-of-the-art resources. It is an important step towards future satellite-based quantum teleportation and paves the way for establishing a worldwide quantum communication network.
authors.affiliation: Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria. Xiaosong.Ma@univie.ac.at
authors.forename: Xiao-song
authors.initials: XS
authors.lastname: Ma
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kropatschek
authors.forename: William
authors.initials: W
authors.lastname: Naylor
authors.forename: Thomas
authors.initials: T
authors.lastname: Scheidl
authors.forename: Johannes
authors.initials: J
authors.lastname: Kofler
authors.forename: Thomas
authors.initials: T
authors.lastname: Herbst
authors.forename: Anton
authors.initials: A
authors.lastname: Zeilinger
authors.forename: Rupert
authors.initials: R
authors.lastname: Ursin
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D055096:Optical Devices; D011789:Quantum Theory; D012542:Scattering, Radiation; D013685:Telecommunications / Q000295:instrumentation*