title: Differential-phase-shift quantum key distribution experiment with a planar light-wave circuit Mach-Zehnder interferometer.
abstract: A differential-phase-shift quantum key distribution experiment was carried out with a planar light-wave circuit (PLC) Mach-Zehnder interferometer. This scheme has two advantages: it requires no polarization control and has a high repetition frequency, provided that a stable interferometer is available. Stable polarization-insensitive operation was achieved with an interferometer fabricated by PLC technology. Raw key creation at a rate of 3076 bits/s with a 5.0% quantum bit-error rate was achieved over 20 km of fiber. The stability of the PLC interferometer was examined.
authors.affiliation: NTT Basic Research Laboratories, NTT Corporation, Atsugi-shi 243-0198, Japan. honjo@will.brl.ntt.co.jp
authors.forename: T
authors.initials: T
authors.lastname: Honjo
authors.forename: K
authors.initials: K
authors.lastname: Inoue
authors.forename: H
authors.initials: H
authors.lastname: Takahashi