Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Modern Optics

A Quantum Key Distribution Channel Based on Optical Fibre

Paul D. Townsend, I. Thompson

Published Dec 1, 1994• 17 citations
Publisher

Abstract

We describe a prototype quantum key distribution system based on standard optical communication fibre and components. The system has been used to transmit pseudo-random bit sequences encoded in the phase of quasi-single-photon pulses over a distance of 10 km. Bit sequences containing about 150 bits were transmitted in bursts 2 ms long with acceptable error rates of about 5%.

DOI
10.1080/09500349414552271

Related papers

Quantum key distribution over a 48 km optical fibre network

Richard Hughes, George L. Morgan, Charles G. Peterson

The secure distribution of the secret random bit sequences known as ‘key’ material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is a new technique for secure key distribution with single-photon transmissions: Heisenberg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal photon states to generate shared key material over multikilometre optical fibre paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. Here we report the most recent results of our optical fibre experiment in which we have performed quantum key distribution over a 48 km optical fibre network at Los Alamos using photon interference states with the B92 and BB84 quantum key distribution protocols.

arXiv:quant-ph/9904038•Journal of Modern Optics•Feb 1, 2000•188 citations

Quantum key distribution over 10 km of optical fiber

Paul D. Townsend

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.

•May 8, 1994•0 citations

Secure Communications Using Quantum Cryptography

Richard Hughes, Buttler, William T., Kwiat, Paul G. +5 more

The secure distribution of the secret random bit sequences known as {open_quotes}key{close_quotes} material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over {open_quotes}open{close_quotes} multi-km node-to-node optical fiber communications links is possible. We have also constructed a quantum key distribution system for free-space, line-of-sight transmission using single-photon polarization states, which is currently undergoing laboratory testing. 7 figs.

•Jan 1, 1997•2 citations

Secure communications using quantum cryptography

Richard Hughes, W. T. Buttler, Paul G. Kwiat +5 more

The secure distribution of the secret random bit sequences known as `key' material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions: Heisenburg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single- photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over `open' multi-km node-to-node optical fiber communications links is possible.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 1, 1997•24 citations

Secure key distribution system based on quantumcryptography

Paul D. Townsend

The secure transmission of cryptographic keys is demonstrated over a 10 km-long optical fibre channel using a technique called ‘quantum cryptography’. Single-photon detector noise and nonideal modulator frequency response lead to error rates of ~6% in the transmitted keys that are corrected using publicly agreed key permutations and parity checks.

Electronics Letters•May 12, 1994•117 citations

Practical quantum key distribution

Hugo Zbinden, Sylvain Fasel, Nicolas Gisin +4 more

Quantum key distribution (QKD) is stepping out of the lab. We present a commercial fibre-optic QKD-prototype based on faint laser pulses and the results of field tests. Faint laser, single photon and entangled-photon based systems are compared with respect to possible bit rates, detector noise and security and their possible implementation in a commercial apparatus.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 11, 2002•1 citation
We describe a prototype quantum key distribution system based on standard optical communication fibre and components. The system has been used to transmit pseudo-random bit sequences encoded in the phase of quasi-single-photon pulses over a distance of 10 km. Bit sequences containing about 150 bits were transmitted in bursts 2 ms long with acceptable error rates of about 5%.
The secure distribution of the secret random bit sequences known as ‘key’ material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is a new technique for secure key distribution with single-photon transmissions: Heisenberg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal photon states to generate shared key material over multikilometre optical fibre paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. Here we report the most recent results of our optical fibre experiment in which we have performed quantum key distribution over a 48 km optical fibre network at Los Alamos using photon interference states with the B92 and BB84 quantum key distribution protocols.
The secure distribution of the secret random bit sequences known as {open_quotes}key{close_quotes} material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over {open_quotes}open{close_quotes} multi-km node-to-node optical fiber communications links is possible. We have also constructed a quantum key distribution system for free-space, line-of-sight transmission using single-photon polarization states, which is currently undergoing laboratory testing. 7 figs.
The secure distribution of the secret random bit sequences known as `key' material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions: Heisenburg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single- photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over `open' multi-km node-to-node optical fiber communications links is possible.