Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1308.1011 · Optics Express

Maintenance-free operation of WDM quantum key distribution system through a field fiber over 30 days

Ken-ichiro Yoshino, Takao Ochi, Mikio Fujiwara, Masahide Sasaki, Akio Tajima

Published Dec 12, 2013• 76 citations
arXivHTMLPDF

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.

DOI
10.1364/oe.21.031395

Related papers

Long-term field demonstration of WDM quantum key distribution system with stabilization control

K. Yoshino, Takao Ochi, Mikio Fujiwara +3 more

A wavelength-division multiplexing quantum key distribution system with stabilization control was demonstrated through a 22-km field fiber in five-day continuous operation. Quantum bit error rates were kept below 3% in all key blocks.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jun 1, 2013•1 citation

Field demonstration of high-speed wavelength-division multiplexing quantum key distribution system and its stabilized operation

K. Yoshino, Mikio Fujiwara, Akihiro Tanaka +8 more

A high-speed quantum key distribution system with the wavelength-division multiplexing was demonstrated in 12hour continuous operation. We achieved a secure key rate of 208 kbps through a 45-km field fiber with 14.5-dB loss.

Opto-Electronics and Communications Conference (OECC)•Jul 1, 2012•0 citations

Quantum key distribution for 10 Gb/s dense wavelength division multiplexing networks

K. A. Patel, J. F. Dynes, Marco Lucamarini +5 more

We demonstrate quantum key distribution (QKD) with bidirectional 10 Gb/s classical data channels in a single fiber using dense wavelength division multiplexing. Record secure key rates of 2.38 Mbps and fiber distances up to 70 km are achieved. Data channels are simultaneously monitored for error-free operation. The robustness of QKD is further demonstrated with a secure key rate of 445 kbps over 25 km, obtained in the presence of data lasers launching conventional 0 dBm power. We discuss the fundamental limit for the QKD performance in the multiplexing environment.

arXiv:1402.1508•Applied Physics Letters•Feb 3, 2014•195 citations

High-speed wavelength-division multiplexing quantum key distribution system

K. Yoshino, Mikio Fujiwara, Akihiro Tanaka +8 more

A high-speed quantum key distribution system was developed with the wavelength-division multiplexing (WDM) technique and dedicated key distillation hardware engines. Two interferometers for encoding and decoding are shared over eight wavelengths to reduce the system's size, cost, and control complexity. The key distillation engines can process a huge amount of data from the WDM channels by using a 1 Mbit block in real time. We demonstrated a three-channel WDM system that simultaneously uses avalanche photodiodes and superconducting single-photon detectors. We achieved 12 h continuous key generation with a secure key rate of 208 kilobits per second through a 45 km field fiber with 14.5 dB loss.

Optics Letters•Jan 13, 2012•80 citations

Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength division multiplexing clock synchronization

Akihiro Tanaka, Mikio Fujiwara, Sae Woo Nam +10 more

We demonstrated ultra fast BB84 quantum key distribution (QKD) transmission at 625 MHz clock rate through a 97 km field-installed fiber using practical clock synchronization based on wavelength-division multiplexing (WDM). We succeeded in over-one-hour stable key generation at a high sifted key rate of 2.4 kbps and a low quantum bit error rate (QBER) of 2.9%. The asymptotic secure key rate was estimated to be 0.78- 0.82 kbps from the transmission data with the decoy method of average photon numbers 0, 0.15, and 0.4 photons/pulse.

arXiv:0805.2193•Optics Express•Jul 14, 2008•120 citations

High-Speed Quantum Key Distribution System for 1-Mbps Real-Time Key Generation

Akihiro Tanaka, Mikio Fujiwara, K. Yoshino +8 more

A high-speed quantum key distribution (QKD) system has been developed with the goal of a 1-Mbps final secure key generation rate under 10-dB transmission loss, which corresponds to 50 km of standard single mode fiber. For the purpose of speeding-up all processes in QKD sequence, we apply a wavelength-division-multiplexing (WDM) technique using the colorless interferometric technique and a key distillation hardware (HW) engine. We establish a novel WDM scheme, sharing interferometers and their temperature regulators over multiple channels, which enables us to increase the number of channels with a small impact on system cost and size. To generate a secure key while satisfying both high speed and high security, we develop a key distillation HW engine which enables us to execute key distillation with 1-Mbit code length in real time. We have experimentally evaluated the performance of the developed system through installed fiber. By operating three wavelength channels, a new, world leading key generation rate of greater than 200 kbps over a 14.5-dB transmission loss has been achieved.

IEEE Journal of Quantum Electronics•Feb 10, 2012•101 citations
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.
We demonstrate quantum key distribution (QKD) with bidirectional 10 Gb/s classical data channels in a single fiber using dense wavelength division multiplexing. Record secure key rates of 2.38 Mbps and fiber distances up to 70 km are achieved. Data channels are simultaneously monitored for error-free operation. The robustness of QKD is further demonstrated with a secure key rate of 445 kbps over 25 km, obtained in the presence of data lasers launching conventional 0 dBm power. We discuss the fundamental limit for the QKD performance in the multiplexing environment.
A high-speed quantum key distribution system was developed with the wavelength-division multiplexing (WDM) technique and dedicated key distillation hardware engines. Two interferometers for encoding and decoding are shared over eight wavelengths to reduce the system's size, cost, and control complexity. The key distillation engines can process a huge amount of data from the WDM channels by using a 1 Mbit block in real time. We demonstrated a three-channel WDM system that simultaneously uses avalanche photodiodes and superconducting single-photon detectors. We achieved 12 h continuous key generation with a secure key rate of 208 kilobits per second through a 45 km field fiber with 14.5 dB loss.
We demonstrated ultra fast BB84 quantum key distribution (QKD) transmission at 625 MHz clock rate through a 97 km field-installed fiber using practical clock synchronization based on wavelength-division multiplexing (WDM). We succeeded in over-one-hour stable key generation at a high sifted key rate of 2.4 kbps and a low quantum bit error rate (QBER) of 2.9%. The asymptotic secure key rate was estimated to be 0.78- 0.82 kbps from the transmission data with the decoy method of average photon numbers 0, 0.15, and 0.4 photons/pulse.
A high-speed quantum key distribution (QKD) system has been developed with the goal of a 1-Mbps final secure key generation rate under 10-dB transmission loss, which corresponds to 50 km of standard single mode fiber. For the purpose of speeding-up all processes in QKD sequence, we apply a wavelength-division-multiplexing (WDM) technique using the colorless interferometric technique and a key distillation hardware (HW) engine. We establish a novel WDM scheme, sharing interferometers and their temperature regulators over multiple channels, which enables us to increase the number of channels with a small impact on system cost and size. To generate a secure key while satisfying both high speed and high security, we develop a key distillation HW engine which enables us to execute key distillation with 1-Mbit code length in real time. We have experimentally evaluated the performance of the developed system through installed fiber. By operating three wavelength channels, a new, world leading key generation rate of greater than 200 kbps over a 14.5-dB transmission loss has been achieved.