Quantum key distribution (QKD) channels are typically realized by transmitting and detecting single photons, and therefore suffer from dramatic reductions in throughput due to both channel loss and noise. These shortcomings can be mitigated by applying telecommunications clock-recovery techniques to maximize the bandwidth of the single-photon channel and minimize the system s exposure to noise. We demonstrate a QKD system operating continuously at a quantum-channel transmission rate of 1.25 GHz, with dedicated data-handling hardware and error-correction/privacy amplification. We discuss the design and performance of our system and highlight issues which limit our maximum transmission and key production rates.
Proceedings Title: SPIE Photonics West 2009 OPTO: Integrated Optoelectronic Devices
Conference Dates: January 19-24, 2009
Conference Location: San Jose, CA
Pub Type: Conferences
free-space optical communication, quantum key distribution, single-photon