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Quantum Key Distribution System Operating at Sifted-Key Rate over 4 Mbit/s



Xiao Tang, Lijun Ma, Alan Mink, Anastase Nakassis, Hai Xu, Barry J. Hershman, Joshua Bienfang, David H. Su, Ronald Boisvert, Charles W. Clark, Carl J. Williams


A complete fiber-based polarization encoding quantum key distribution (QKD) system based on the BB84 protocol has been developed at National Institute of Standard and Technology (NIST). The system can be operated at a sifted key rate of more than 4 Mbit/s over optical fiber of length 1 km and mean photon number 0.1. The quantum channel uses 850 nm photons from attenuated high speed VCSELs and the classical channel uses 1550 nm light from normal commercial coarse wavelength division multiplexing devices. Sifted-key rates and quantum error rates at different transmission rates are measured as a function of distance (fiber length). A polarization auto-compensation module has been developed and utilized to recover the polarization state and to compensate for temporal drift. An automatic timing alignment device has also been developed to quickly handle the initial configuration of quantum channels so that detection events fall into the correct timing window. These automated functions make the system more practical for integration into existing optical local area networks.
Conference Dates
April 18-21, 2006
Conference Location
Conference Title
SPIE Defense and Security Conference


automatic timing alignment, BB84 protocol, polarization auto-compensation, quantum key distribution


Tang, X. , Ma, L. , Mink, A. , Nakassis, A. , Xu, H. , Hershman, B. , Bienfang, J. , Su, D. , Boisvert, R. , Clark, C. and Williams, C. (2006), Quantum Key Distribution System Operating at Sifted-Key Rate over 4 Mbit/s, SPIE Defense and Security Conference, , USA, [online], (Accessed May 24, 2024)


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Created June 18, 2006, Updated October 12, 2021