Abstract

Quantum cryptography is an important new technique for the distribution of cryptographic keys that exploits the quantum properties of single photons to guarantee the secrecy of the key.‘^…’ Here, we report the transmission over 10 km of optical fiber of pseudorandom bit sequences (PRBS) encoded in the phase of faint pulses of light that contain substantially less than one photon on average. This demonstrates many of the properties required for practical quantum-key distribution systems.

© 1994 Optical Society of America