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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
100 km differential phase shift quantum key distribution experiment with low jitter up-conversion detectors
Optics Express
|June 18, 2009
Summary
We achieved secure quantum key distribution over 100 km of optical fiber using the differential phase shift protocol. This experiment demonstrates practical, high-speed secure key generation against quantum eavesdropping attacks.
Area of Science:
- Quantum Information Science
- Quantum Cryptography
- Optical Communications
Background:
- Quantum key distribution (QKD) offers information-theoretic security.
- Previous QKD experiments faced limitations in distance and practical key generation rates.
- Individual eavesdropping attacks remain a significant concern in QKD security.
Purpose of the Study:
- To demonstrate secure quantum key distribution over extended fiber optic links.
- To implement and evaluate the differential phase shift QKD protocol with advanced single-photon detectors.
- To achieve practical secure key generation rates at a distance of 100 km.
Main Methods:
- Utilized the differential phase shift quantum key distribution protocol.
- Employed low timing jitter 1.55 micrometer single-photon detectors.
- Integrated frequency up-conversion in periodically poled lithium niobate waveguides and silicon avalanche photodiodes.
- Conducted security analysis against general individual quantum attacks.
Main Results:
- Successfully distributed quantum keys secure against individual eavesdropping attacks over 100 km of optical fiber.
- Generated secure keys at a practical rate of 166 bit/s over 100 km.
- Achieved a sifted key generation rate of 2 Mbit/s over 10 km using low jitter detectors.
Conclusions:
- The differential phase shift QKD protocol is viable for long-distance, secure key distribution.
- Advanced single-photon detector technology significantly enhances QKD performance.
- This work represents a practical advancement in secure communication over optical fiber networks.
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