The quantum key distribution system uses wavelength conversion - from transmission/ telecom wavelengths (1310 nm) to wavelengths suitable for use with silicon-based detectors (710 nm). The resulting system provides a secure key rate of 500 kbit/s at 10 km and 9.1 kbit/s at 50 km at 625 MHz.

Image Caption: National Institute of Standards and Technology (NIST)