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Title: 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:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [1]; ORCiD logo [3]; ORCiD logo [4]
  1. Duke Univ., Durham, NC (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); National Univ. of Singapore (Singapore)
  3. Duke Univ., Durham, NC (United States); IonQ Inc., College Park, MD (United States)
  4. 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:
Journal Article: 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. doi: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. doi: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 = {Fri Nov 24 00:00:00 EST 2017},
month = {Fri Nov 24 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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