# Unconditionally secure quantum key distribution over 50 km of standard telecom fibre

@article{Gobby2004UnconditionallySQ, title={Unconditionally secure quantum key distribution over 50 km of standard telecom fibre}, author={C. Gobby and Z. L. Yuan and Andrew J. Shields}, journal={Electronics Letters}, year={2004}, volume={40}, pages={1603-1605} }

A weak pulse quantum key distribution system is presented, which is secure against all individual attacks, including photon number splitting. By carefully controlling the weak pulse intensity the maximum secure bit rate as a function of the fibre length is demonstrated. Unconditionally secure keys can be formed for standard telecom fibres exceeding 50 km in length.

## 54 Citations

Decoy pulse quantum key distribution for practical purposes

- Computer Science
- 2008

The random bits from the secure keys are found to pass stringent statistical tests and the decoy pulse protocol employed uses two weak pulses (signal and decoy) and one vacuum pulse.

Practical quantum key distribution over 60 hours at an optical fiber distance of 20km using weak and vacuum decoy pulses for enhanced security.

- Physics, MedicineOptics express
- 2007

This work demonstrates an experimental one-way decoy pulse quantum key distribution running continuously for 60 hours over a fiber distance of 20km and obtains the highest rate reported using this decoy protocol over this fiber distance and duration.

Unconditionally secure one-way quantum key distribution using decoy pulses

- Physics2007 Quantum Electronics and Laser Science Conference
- 2007

Experimental one-way decoy quantum key distribution (QKD) is reported as a function of distance up to 25.3km. The high key rates obtained exceed one order of magnitude more than QKD performed without…

Unconditionally secure one-way quantum key distribution using decoy pulses

- PhysicsQELS 2007
- 2007

Experimental one-way decoy quantum key distribution (QKD) is reported as a function of distance up to 25.3km. The high key rates obtained exceed one order of magnitude more than QKD performed without…

Secure Communication with One Decoy State and Two Way Quantum Key Distribution Scheme

- Mathematics
- 2013

Quantum Key Distribution (QKD) provides a mean for unconditionally secure secret key sharing for secure communication. For a practical QKD system, the recently proposed decoy state protocol has…

Fast and long-distance differential-phase-shift quantum key distribution

- Physics2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference
- 2006

A differential-phase-shift quantum key distribution experiment employing up-conversion single-photon detectors is presented. We achieved a 1-Mbit/s sifted key rate over a 20-km optical fiber, and…

Continuous operation of a one-way quantum key distribution system over installed telecom fibre.

- Physics, MedicineOptics express
- 2005

A robust, compact and automated quantum key distribution system, based upon a one-way Mach-Zender interferometer, which is actively compensated for temporal drifts in the photon phase and polarization is demonstrated, suggesting that actively compensated QKD systems are suitable for practical applications.

Long-distance quantum key distribution in optical fibre

- Physics
- 2006

Use of low-noise detectors can both increase the secret bit rate of long-distance quantum key distribution (QKD) and dramatically extend the length of a fibre optic link over which secure keys can be…

Differential phase shift quantum key distribution experiment over 105 km fibre

- Physics
- 2005

We report a quantum key distribution experiment based on the differential phase shift keying (DPSK) protocol with a Poissonian photon source, in which secure keys were generated over >100 km fibre…

100 km differential phase shift quantum key distribution experiment with low jitter up-conversion detectors.

- Physics, MedicineOptics express
- 2006

A quantum key distribution experiment in which keys that were secure against all individual eavesdropping attacks allowed by quantum mechanics were distributed over 100 km of optical fiber using low timing jitter 1.55 microm single-photon detectors.

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