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Title: Coherent-state quantum key distribution without random basis switching

Abstract

The random switching of measurement bases is commonly assumed to be a necessary step of quantum key distribution protocols. In this paper we present a no-switching protocol and show that switching is not required for coherent-state continuous-variable quantum key distribution. Further, this protocol achieves higher information rates and a simpler experimental setup compared to previous protocols that rely on switching. We propose an optimal eavesdropping attack against this protocol, assuming individual Gaussian attacks. Finally, we investigate and compare the no-switching protocol applied to the original Bennett-Brassard 1984 scheme.

Authors:
 [1];  [2]; ; ; ;  [1];  [3]
  1. Quantum Optics Group, Department of Physics, Faculty of Science, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)
  2. (Australia)
  3. Department of Physics, University of Queensland, St Lucia, Queensland 4072 (Australia)
Publication Date:
OSTI Identifier:
20974532
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.022316; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISTRIBUTION; EIGENSTATES; INFORMATION THEORY; QUANTUM CRYPTOGRAPHY; RANDOMNESS

Citation Formats

Weedbrook, Christian, Department of Physics, University of Queensland, St Lucia, Queensland 4072, Lance, Andrew M., Bowen, Warwick P., Symul, Thomas, Lam, Ping Koy, and Ralph, Timothy C.. Coherent-state quantum key distribution without random basis switching. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.022316.
Weedbrook, Christian, Department of Physics, University of Queensland, St Lucia, Queensland 4072, Lance, Andrew M., Bowen, Warwick P., Symul, Thomas, Lam, Ping Koy, & Ralph, Timothy C.. Coherent-state quantum key distribution without random basis switching. United States. doi:10.1103/PHYSREVA.73.022316.
Weedbrook, Christian, Department of Physics, University of Queensland, St Lucia, Queensland 4072, Lance, Andrew M., Bowen, Warwick P., Symul, Thomas, Lam, Ping Koy, and Ralph, Timothy C.. Wed . "Coherent-state quantum key distribution without random basis switching". United States. doi:10.1103/PHYSREVA.73.022316.
@article{osti_20974532,
title = {Coherent-state quantum key distribution without random basis switching},
author = {Weedbrook, Christian and Department of Physics, University of Queensland, St Lucia, Queensland 4072 and Lance, Andrew M. and Bowen, Warwick P. and Symul, Thomas and Lam, Ping Koy and Ralph, Timothy C.},
abstractNote = {The random switching of measurement bases is commonly assumed to be a necessary step of quantum key distribution protocols. In this paper we present a no-switching protocol and show that switching is not required for coherent-state continuous-variable quantum key distribution. Further, this protocol achieves higher information rates and a simpler experimental setup compared to previous protocols that rely on switching. We propose an optimal eavesdropping attack against this protocol, assuming individual Gaussian attacks. Finally, we investigate and compare the no-switching protocol applied to the original Bennett-Brassard 1984 scheme.},
doi = {10.1103/PHYSREVA.73.022316},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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