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Updated: Jun 21, 2026
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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Gigahertz decoy quantum key distribution with 1 Mbit/s secure key rate
A R Dixon1, Z L Yuan, J F Dynes
1Toshiba Research Europe Ltd, Cambridge Research Laboratory, Cambridge, UK.
Optics Express
|July 8, 2009
Summary
This study introduces the first gigahertz-clocked quantum key distribution (QKD) system. It achieves record key rates using advanced single-photon detectors, paving the way for practical, low-cost secure communication.
Area of Science:
- Quantum Information Science
- Quantum Cryptography
- Photonics
Background:
- Quantum Key Distribution (QKD) offers information-theoretically secure communication.
- High-speed single-photon detection is crucial for practical QKD systems.
- Existing QKD systems often face limitations in speed and cost.
Purpose of the Study:
- To report the development of the first gigahertz-clocked decoy-protocol quantum key distribution (QKD) system.
- To demonstrate record key rates utilizing novel high-speed single-photon detectors.
- To explore the potential for practical and cost-effective QKD solutions.
Main Methods:
- Implementation of a gigahertz-clocked decoy-protocol QKD system.
- Utilization of self-differencing Indium Gallium Arsenide (InGaAs) avalanche photodiodes for high-speed single-photon detection.
- Characterization of secure key rates over varying fiber optic distances.
Main Results:
- Achieved a secure key rate of 1.02 Mbit/s over a 20 km fiber distance.
- Demonstrated a secure key rate of 10.1 kbit/s over a 100 km fiber distance.
- Successfully operated the QKD system at gigahertz clock speeds.
Conclusions:
- The developed QKD system achieves unprecedented key rates at high clock speeds.
- The use of compact, non-cryogenic detectors enables practical and potentially low-cost QKD.
- This advancement facilitates the integration of secure QKD for broadband communication networks.
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