title: 1310-nm quantum key distribution system with up-conversion pump wavelength at 1550 nm.
abstract: We show that the performance of a 1310-nm quantum key distribution (QKD) system with up-conversion detectors pumped at 1550 nm is comparable with or better than that of current 1550-nm QKD systems with a pump at shorter wavelength. The nonlinearly-induced dark counts are reduced when the wavelength of the pump light is longer than that of the quantum signal. We have developed a 1550-nm pump up-conversion detector for a 1310-nm QKD system, and we experimentally study the polarization sensitivity, pump-signal format, and various influences on the dark count rate. Using this detector in a proof-of-principle experiment, we have achieved a secure key rate of 500 kbit/s at 10 km and 9.1 kbit/s at 50 km in a 625-MHz, B92, polarization-coding QKD system, and we expect that the system performance could be improved further.
authors: Hai
authors: H
authors: Xu
authors: Lijun
authors: L
authors: Ma
authors: Alan
authors: A
authors: Mink
authors: Barry
authors: B
authors: Hershman
authors: Xiao
authors: X
authors: Tang