title: Maintenance-free operation of WDM quantum key distribution system through a field fiber over 30 days.
abstract: Maintenance-free wavelength-division-multiplexing quantum key distribution for 30 days was achieved through a 22-km field fiber. Using polarization-independent interferometers and stabilization techniques, we attained a quantum bit error rate as low as 1.70% and an estimated secure key rate as high as 112.4 kbps for a record-breaking 291.3 Gbits of estimated secure keys accumulated over an uninterrupted operation period.
authors: Ken-ichiro
authors: K
authors: Yoshino
authors: Takao
authors: T
authors: Ochi
authors: Mikio
authors: M
authors: Fujiwara
authors: Masahide
authors: M
authors: Sasaki
authors: Akio
authors: A
authors: Tajima