title: Ultrafast and fault-tolerant quantum communication across long distances.
abstract: Quantum repeaters (QRs) provide a way of enabling long distance quantum communication by establishing entangled qubits between remote locations. In this Letter, we investigate a new approach to QRs in which quantum information can be faithfully transmitted via a noisy channel without the use of long distance teleportation, thus eliminating the need to establish remote entangled links. Our approach makes use of small encoding blocks to fault-tolerantly correct both operational and photon loss errors. We describe a way to optimize the resource requirement for these QRs with the aim of the generation of a secure key. Numerical calculations indicate that the number of quantum memory bits at each repeater station required for the generation of one secure key has favorable polylogarithmic scaling with the distance across which the communication is desired.
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA.
authors.forename: Sreraman
authors.initials: S
authors.lastname: Muralidharan
authors.affiliation: Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, USA.
authors.forename: Jungsang
authors.initials: J
authors.lastname: Kim
authors.affiliation: Institute of Quantum computing, University of Waterloo, N2L 3G1 Waterloo, Canada.
authors.forename: Norbert
authors.initials: N
authors.lastname: Lütkenhaus
authors.affiliation: Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors.forename: Mikhail D
authors.initials: MD
authors.lastname: Lukin
authors.affiliation: Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Jiang