skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Passive decoy-state quantum key distribution with practical light sources

Abstract

Decoy states have been proven to be a very useful method for significantly enhancing the performance of quantum key distribution systems with practical light sources. Although active modulation of the intensity of the laser pulses is an effective way of preparing decoy states in principle, in practice passive preparation might be desirable in some scenarios. Typical passive schemes involve parametric down-conversion. More recently, it has been shown that phase-randomized weak coherent pulses (WCP) can also be used for the same purpose [M. Curty et al., Opt. Lett. 34, 3238 (2009).] This proposal requires only linear optics together with a simple threshold photon detector, which shows the practical feasibility of the method. Most importantly, the resulting secret key rate is comparable to the one delivered by an active decoy-state setup with an infinite number of decoy settings. In this article we extend these results, now showing specifically the analysis for other practical scenarios with different light sources and photodetectors. In particular, we consider sources emitting thermal states, phase-randomized WCP, and strong coherent light in combination with several types of photodetectors, like, for instance, threshold photon detectors, photon number resolving detectors, and classical photodetectors. Our analysis includes as well the effect thatmore » detection inefficiencies and noise in the form of dark counts shown by current threshold detectors might have on the final secret key rate. Moreover, we provide estimations on the effects that statistical fluctuations due to a finite data size can have in practical implementations.« less

Authors:
 [1];  [2];  [3];  [2]
  1. ETSI Telecomunicacion, Department of Signal Theory and Communications, University of Vigo, Campus Universitario, E-36310 Vigo (Pontevedra) (Spain)
  2. Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, N2L 3G1 Waterloo, Ontario (Canada)
  3. Center for Quantum Information and Quantum Control, Department of Physics and Department of Electrical and Computer Engineering, University of Toronto, M5S 3G4 Toronto, Ontario (Canada)
Publication Date:
OSTI Identifier:
21408201
Resource Type:
Journal Article
Journal Name:
Physical Review. A
Additional Journal Information:
Journal Volume: 81; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.81.022310; (c) 2010 The American Physical Society; Journal ID: ISSN 1050-2947
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISTRIBUTION; FLUCTUATIONS; LASERS; MODULATION; NOISE; OPTICS; PERFORMANCE; PHOTODETECTORS; PHOTONS; PULSES; THRESHOLD DETECTORS; VISIBLE RADIATION; BOSONS; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; MASSLESS PARTICLES; MEASURING INSTRUMENTS; NEUTRON DETECTORS; RADIATION DETECTORS; RADIATIONS; VARIATIONS

Citation Formats

Curty, Marcos, Ma, Xiongfeng, Qi, Bing, Moroder, Tobias, Quantum Information Theory Group, Institute of Theoretical Physics I, University of Erlangen-Nuernberg, D-91058 Erlangen, and Max Planck Institute for the Science of Light, D-91058 Erlangen. Passive decoy-state quantum key distribution with practical light sources. United States: N. p., 2010. Web. doi:10.1103/PHYSREVA.81.022310.
Curty, Marcos, Ma, Xiongfeng, Qi, Bing, Moroder, Tobias, Quantum Information Theory Group, Institute of Theoretical Physics I, University of Erlangen-Nuernberg, D-91058 Erlangen, & Max Planck Institute for the Science of Light, D-91058 Erlangen. Passive decoy-state quantum key distribution with practical light sources. United States. https://doi.org/10.1103/PHYSREVA.81.022310
Curty, Marcos, Ma, Xiongfeng, Qi, Bing, Moroder, Tobias, Quantum Information Theory Group, Institute of Theoretical Physics I, University of Erlangen-Nuernberg, D-91058 Erlangen, and Max Planck Institute for the Science of Light, D-91058 Erlangen. 2010. "Passive decoy-state quantum key distribution with practical light sources". United States. https://doi.org/10.1103/PHYSREVA.81.022310.
@article{osti_21408201,
title = {Passive decoy-state quantum key distribution with practical light sources},
author = {Curty, Marcos and Ma, Xiongfeng and Qi, Bing and Moroder, Tobias and Quantum Information Theory Group, Institute of Theoretical Physics I, University of Erlangen-Nuernberg, D-91058 Erlangen and Max Planck Institute for the Science of Light, D-91058 Erlangen},
abstractNote = {Decoy states have been proven to be a very useful method for significantly enhancing the performance of quantum key distribution systems with practical light sources. Although active modulation of the intensity of the laser pulses is an effective way of preparing decoy states in principle, in practice passive preparation might be desirable in some scenarios. Typical passive schemes involve parametric down-conversion. More recently, it has been shown that phase-randomized weak coherent pulses (WCP) can also be used for the same purpose [M. Curty et al., Opt. Lett. 34, 3238 (2009).] This proposal requires only linear optics together with a simple threshold photon detector, which shows the practical feasibility of the method. Most importantly, the resulting secret key rate is comparable to the one delivered by an active decoy-state setup with an infinite number of decoy settings. In this article we extend these results, now showing specifically the analysis for other practical scenarios with different light sources and photodetectors. In particular, we consider sources emitting thermal states, phase-randomized WCP, and strong coherent light in combination with several types of photodetectors, like, for instance, threshold photon detectors, photon number resolving detectors, and classical photodetectors. Our analysis includes as well the effect that detection inefficiencies and noise in the form of dark counts shown by current threshold detectors might have on the final secret key rate. Moreover, we provide estimations on the effects that statistical fluctuations due to a finite data size can have in practical implementations.},
doi = {10.1103/PHYSREVA.81.022310},
url = {https://www.osti.gov/biblio/21408201}, journal = {Physical Review. A},
issn = {1050-2947},
number = 2,
volume = 81,
place = {United States},
year = {Mon Feb 15 00:00:00 EST 2010},
month = {Mon Feb 15 00:00:00 EST 2010}
}