title: 10-GHz clock differential phase shift quantum key distribution experiment.
abstract: This paper reports the first quantum key distribution experiment implemented with a 10-GHz clock frequency. We used a 10-GHz actively mode-locked fiber laser as a source of short coherent pulses and single photon detectors based on frequency up-conversion in periodically poled lithium niobate waveguides. The use of short pulses and low-jitter upconversion detectors significantly reduced the bit errors caused by detector dark counts even after long-distance transmission of a weak coherent state pulse. We employed the differential phase shift quantum key distribution protocol, and generated sifted keys at a rate of 3.7 kbit/s over a 105 km fiber with a bit error rate of 9.7%.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takesue
authors.forename: Eleni
authors.initials: E
authors.lastname: Diamanti
authors.forename: Carsten
authors.initials: C
authors.lastname: Langrock
authors.forename: M M
authors.initials: MM
authors.lastname: Fejer
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Yamamoto