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Quantum key distribution at 1550 nm with twin superconducting single-photon detectors



Robert Hadfield, Jonathan L. Habif, John Schlafer, Robert E. Schwall, Sae Woo Nam


The authors report on the full implementation of a superconducting detector technology in a fiber-based quantum key distribution (QKD) link. Nanowire-based superconducting single-photon detectors (SSPDs) offer single-photon detection with low dark counts, low jitter, and short recovery times. These detectors are highly promising candidates for future high key rate QKD links operating at 1550 nm. The authors use twin SSPDs to perform the BB84 protocol in a 1550 nm fiber-based QKD link clocked at 3.3 MHz. They exchange secure key over a distance of 42.5 km in telecom fiber and demonstrate that secure key can be transmitted over a total link loss exceeding 12 dB.
Applied Physics Letters


quantum communication, quantum cryptography, quantum key distribution, single photon detector, superconducting detector


Hadfield, R. , Habif, J. , Schlafer, J. , Schwall, R. and Nam, S. (2006), Quantum key distribution at 1550 nm with twin superconducting single-photon detectors, Applied Physics Letters, [online], (Accessed April 15, 2024)
Created December 14, 2006, Updated October 12, 2021