Quantum key distribution at 1550nm with twin superconducting single-photon detectors
Robert H. Hadfield, Jonathan L. Habif, J. Schlafer, Robert E. Schwall, Sae Woo Nam · Applied Physics Letters · 2006
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 infrared 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 1550nm. The authors use twin SSPDs to perform the BB84 protocol in a 1550nm fiber-based QKD link clocked at 3.3MHz. They exchange secure key over a distance of 42.5km in telecom fiber and demonstrate that secure key can be transmitted over a total link loss exceeding 12dB.