# Practical free-space quantum key distribution over 10 km in daylight and at night

@article{Hughes2002PracticalFQ, title={Practical free-space quantum key distribution over 10 km in daylight and at night}, author={Richard J. Hughes and Jane E. Nordholt and Derek Derkacs and Charles G. Peterson}, journal={New Journal of Physics}, year={2002}, volume={4}, pages={43-43} }

We have demonstrated quantum key distribution (QKD) (Bennett C H and Brassard G 1984 Proc. IEEE Int. Conf. on Computers, Systems, and Signal Processing (Bangalore, India) p 175) over a 10 km, 1-airmass atmospheric range during daylight and at night. Secret random bit sequences of the quality required for the cryptographic keys used to initialize secure communications devices were transferred at practical rates with realistic security. By identifying the physical parameters that determine the… Expand

#### 438 Citations

Free-space quantum cryptography for metropolitan areas

- Mathematics, Engineering
- SPIE Security + Defence
- 2006

Quantum key distribution (QKD)1 is the first method of quantum information science that will find its way into our everyday life. It employs fundamental laws of quantum physics to ensure provably… Expand

Free-space quantum key distribution over 144 km

- Physics, Engineering
- SPIE Security + Defence
- 2006

We report on the experimental implementation of a BB84-type quantum key distribution protocol over a 144 km free-space link using weak coherent laser pulses. The security was assured by employing… Expand

Free-Space Decoy-State Quantum Key Distribution

- Physics
- OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference
- 2008

Quantum cryptography, the only method which can provide quantifiable security of a distributed key, became the first application of quantum information methods. Complementary to fiber based systems,… Expand

High-speed free-space quantum key distribution system for urban daylight applications.

- Computer Science, Medicine
- Applied optics
- 2013

We report a free-space quantum key distribution system designed for high-speed key transmission in urban areas. Clocking the system at gigahertz frequencies and efficiently filtering background… Expand

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… Expand

Implementation of polarization-coded free-space BB84 quantum key distribution

- Physics
- 2008

We report on the implementation of a Bennett-Brassard 1984 quantum key distribution protocol over a free-space optical path on an optical table. Attenuated laser pulses and Pockels cells driven by a… Expand

Faraday-Michelson system for quantum cryptography.

- Physics, Medicine
- Optics letters
- 2005

A unidirectional intrinsically stable scheme that is based on Michelson-Faraday interferometers, in which ordinary mirrors are replaced with 90 degree Faraday mirrors is presented, which is to the authors' knowledge the longest reported quantum key distribution experiment under field conditions. Expand

Low cost and compact quantum key distribution

- Physics
- 2006

We present the design of a novel free-space quantum cryptography system, complete with purpose-built software, that can operate in daylight conditions. The transmitter and receiver modules are built… Expand

Experimental filtering effect on the daylight operation of a free-space quantum key distribution

- Medicine, Computer Science
- Scientific Reports
- 2018

This study quantitatively analyzes how the performance of the QBER and the key rates changes for different combinations of filtering techniques in a free-space BB84 QKD system in daylight to obtain the maximum secure key rate. Expand

The security of practical quantum key distribution

- Physics
- 2009

Quantum key distribution (QKD) is the first quantum information task to reach the level of mature technology, already fit for commercialization. It aims at the creation of a secret key between… Expand

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