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This content will become publicly available on November 16, 2016

Title: Discrete and continuous variables for measurement-device-independent quantum cryptography

In a recent Article in Nature Photonics, Pirandola et al.1 claim that the achievable secret key rates of discrete-variable (DV) measurementdevice- independent (MDI) quantum key distribution (QKD) (refs 2,3) are “typically very low, unsuitable for the demands of a metropolitan network” and introduce a continuous-variable (CV) MDI QKD protocol capable of providing key rates which, they claim, are “three orders of magnitude higher” than those of DV MDI QKD. We believe, however, that the claims regarding low key rates of DV MDI QKD made by Pirandola et al.1 are too pessimistic. Here in this paper, we show that the secret key rate of DV MDI QKD with commercially available high-efficiency single-photon detectors (SPDs) (for example, see and and good system alignment is typically rather high and thus highly suitable for not only long-distance communication but also metropolitan networks.
 [1] ;  [2] ;  [3] ;  [4] ;  [5]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Research Lab. of Electronics
  2. Univ. of Vigo, Vigo (Spain). Escuela de Ingenieria de Telecomunicacion, Dept. of Signal Theory and Communications
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computational Sciences and Engineering Division
  4. Univ. of Toronto, ON (Canada). Dept. of Electrical & Computer Engineering
  5. Univ. of Toronto, ON (Canada). Dept. of Electrical & Computer Engineering
Publication Date:
OSTI Identifier:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Nature Photonics
Additional Journal Information:
Journal Volume: 9; Journal Issue: 12; Journal ID: ISSN 1749-4885
Nature Publishing Group
Research Org:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
ORNL LDRD Director's R&D
Country of Publication:
United States