title: Long-distance entanglement-based quantum key distribution over optical fiber.
abstract: We report the first entanglement-based quantum key distribution (QKD) experiment over a 100-km optical fiber. We used superconducting single photon detectors based on NbN nanowires that provide high-speed single photon detection for the 1.5-mum telecom band, an efficient entangled photon pair source that consists of a fiber coupled periodically poled lithium niobate waveguide and ultra low loss filters, and planar lightwave circuit Mach-Zehnder interferometers (MZIs) with ultra stable operation. These characteristics enabled us to perform an entanglement-based QKD experiment over a 100-km optical fiber. In the experiment, which lasted approximately 8 hours, we successfully generated a 16 kbit sifted key with a quantum bit error rate of 6.9 % at a rate of 0.59 bits per second, from which we were able to distill a 3.9 kbit secure key.
authors: NTT Basic Research Laboratories, NTT Corporation, Atsugi-shi 243-0198, Japan. honjo@will.brl.ntt.co.jp
authors: T
authors: T
authors: Honjo
authors: S W
authors: SW
authors: Nam
authors: H
authors: H
authors: Takesue
authors: Q
authors: Q
authors: Zhang
authors: H
authors: H
authors: Kamada
authors: Y
authors: Y
authors: Nishida
authors: O
authors: O
authors: Tadanaga
authors: M
authors: M
authors: Asobe
authors: B
authors: B
authors: Baek
authors: R
authors: R
authors: Hadfield
authors: S
authors: S
authors: Miki
authors: M
authors: M
authors: Fujiwara
authors: M
authors: M
authors: Sasaki
authors: Z
authors: Z
authors: Wang
authors: K
authors: K
authors: Inoue
authors: Y
authors: Y
authors: Yamamoto
mesh_terms: D016494:Computer Security / Q000295:instrumentation*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D016247:Information Storage and Retrieval / Q000379:methods*; D055100:Optical Fibers; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*