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Title: Reduced randomness in quantum cryptography with sequences of qubits encoded in the same basis

Abstract

We consider the cloning of sequences of qubits prepared in the states used in the BB84 or six-state quantum cryptography protocol, and show that the single-qubit fidelity is unaffected even if entire sequences of qubits are prepared in the same basis. This result is only valid provided that the sequences are much shorter than the total key. It is of great importance for practical quantum cryptosystems because it reduces the need for high-speed random number generation without impairing on the security against finite-size cloning attacks.

Authors:
;  [1];  [2];  [3];  [4];  [2]
  1. Quantum Information and Communication, Ecole Polytechnique, CP 165, Universite Libre de Bruxelles, 1050 Brussels (Belgium)
  2. Quantum Information Theory group (QUIT), Dipartimento di Fisica 'A. Volta' and INFM - Unita di Pavia, Via Bassi 6, I-27100 Pavia (Italy)
  3. (Italy)
  4. Group of Applied Physics, University of Geneva, 1211 Geneva 4 (Switzerland)
Publication Date:
OSTI Identifier:
20786853
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.032304; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ENERGY LEVELS; QUANTUM COMPUTERS; QUANTUM CRYPTOGRAPHY; QUANTUM MECHANICS; QUBITS; RANDOMNESS; SECRECY PROTECTION; VELOCITY

Citation Formats

Lamoureux, L.-P., Cerf, N. J., Bechmann-Pasquinucci, H., UCCI.IT, via Olmo 26, I-23888 Rovagnate, Gisin, N., and Macchiavello, C. Reduced randomness in quantum cryptography with sequences of qubits encoded in the same basis. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Lamoureux, L.-P., Cerf, N. J., Bechmann-Pasquinucci, H., UCCI.IT, via Olmo 26, I-23888 Rovagnate, Gisin, N., & Macchiavello, C. Reduced randomness in quantum cryptography with sequences of qubits encoded in the same basis. United States. doi:10.1103/PHYSREVA.73.0.
Lamoureux, L.-P., Cerf, N. J., Bechmann-Pasquinucci, H., UCCI.IT, via Olmo 26, I-23888 Rovagnate, Gisin, N., and Macchiavello, C. Wed . "Reduced randomness in quantum cryptography with sequences of qubits encoded in the same basis". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786853,
title = {Reduced randomness in quantum cryptography with sequences of qubits encoded in the same basis},
author = {Lamoureux, L.-P. and Cerf, N. J. and Bechmann-Pasquinucci, H. and UCCI.IT, via Olmo 26, I-23888 Rovagnate and Gisin, N. and Macchiavello, C.},
abstractNote = {We consider the cloning of sequences of qubits prepared in the states used in the BB84 or six-state quantum cryptography protocol, and show that the single-qubit fidelity is unaffected even if entire sequences of qubits are prepared in the same basis. This result is only valid provided that the sequences are much shorter than the total key. It is of great importance for practical quantum cryptosystems because it reduces the need for high-speed random number generation without impairing on the security against finite-size cloning attacks.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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