Provably secure and high-rate quantum key distribution with time-bin qudits
Abstract
The security of conventional cryptography systems is threatened in the forthcoming era of quantum computers. Quantum key distribution (QKD) features fundamentally proven security and offers a promising option for quantum-proof cryptography solution. Although prototype QKD systems over optical fiber have been demonstrated over the years, the key generation rates remain several orders of magnitude lower than current classical communication systems. In an effort toward a commercially viable QKD system with improved key generation rates, we developed a discrete-variable QKD system based on time-bin quantum photonic states that can generate provably secure cryptographic keys at megabit-per-second rates over metropolitan distances. We use high-dimensional quantum states that transmit more than one secret bit per received photon, alleviating detector saturation effects in the superconducting nanowire single-photon detectors used in our system that feature very high detection efficiency (of more than 70%) and low timing jitter (of less than 40 ps). Our system is constructed using commercial off-the-shelf components, and the adopted protocol can be readily extended to free-space quantum channels. In conclusion, the security analysis adopted to distill the keys ensures that the demonstrated protocol is robust against coherent attacks, finite-size effects, and a broad class of experimental imperfections identified in our system.
- Authors:
-
- Duke Univ., Durham, NC (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); National Univ. of Singapore (Singapore)
- Duke Univ., Durham, NC (United States); IonQ Inc., College Park, MD (United States)
- The Ohio State Univ., Columbus, OH (United States)
- Publication Date:
- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1410948
- Grant/Contract Number:
- AC05-00OR22725
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Science Advances
- Additional Journal Information:
- Journal Volume: 3; Journal Issue: 11; Journal ID: ISSN 2375-2548
- Publisher:
- AAAS
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
Citation Formats
Islam, Nurul T., Lim, Charles Ci Wen, Cahall, Clinton, Kim, Jungsang, and Gauthier, Daniel J. Provably secure and high-rate quantum key distribution with time-bin qudits. United States: N. p., 2017.
Web. doi:10.1126/sciadv.1701491.
Islam, Nurul T., Lim, Charles Ci Wen, Cahall, Clinton, Kim, Jungsang, & Gauthier, Daniel J. Provably secure and high-rate quantum key distribution with time-bin qudits. United States. https://doi.org/10.1126/sciadv.1701491
Islam, Nurul T., Lim, Charles Ci Wen, Cahall, Clinton, Kim, Jungsang, and Gauthier, Daniel J. Fri .
"Provably secure and high-rate quantum key distribution with time-bin qudits". United States. https://doi.org/10.1126/sciadv.1701491. https://www.osti.gov/servlets/purl/1410948.
@article{osti_1410948,
title = {Provably secure and high-rate quantum key distribution with time-bin qudits},
author = {Islam, Nurul T. and Lim, Charles Ci Wen and Cahall, Clinton and Kim, Jungsang and Gauthier, Daniel J.},
abstractNote = {The security of conventional cryptography systems is threatened in the forthcoming era of quantum computers. Quantum key distribution (QKD) features fundamentally proven security and offers a promising option for quantum-proof cryptography solution. Although prototype QKD systems over optical fiber have been demonstrated over the years, the key generation rates remain several orders of magnitude lower than current classical communication systems. In an effort toward a commercially viable QKD system with improved key generation rates, we developed a discrete-variable QKD system based on time-bin quantum photonic states that can generate provably secure cryptographic keys at megabit-per-second rates over metropolitan distances. We use high-dimensional quantum states that transmit more than one secret bit per received photon, alleviating detector saturation effects in the superconducting nanowire single-photon detectors used in our system that feature very high detection efficiency (of more than 70%) and low timing jitter (of less than 40 ps). Our system is constructed using commercial off-the-shelf components, and the adopted protocol can be readily extended to free-space quantum channels. In conclusion, the security analysis adopted to distill the keys ensures that the demonstrated protocol is robust against coherent attacks, finite-size effects, and a broad class of experimental imperfections identified in our system.},
doi = {10.1126/sciadv.1701491},
journal = {Science Advances},
number = 11,
volume = 3,
place = {United States},
year = {2017},
month = {11}
}
Web of Science
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Genuine time-bin-encoded quantum key distribution over a turbulent depolarizing free-space channel
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