Quantum stream cipher by the Yuen 2000 protocol: Design and experiment by an intensity-modulation scheme

Journal Article · Mon Aug 15 00:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.72.022335· OSTI ID:20718094

Hirota, Osamu; Sohma, Masaki; Fuse, Masaru; Kato, Kentaro ^[1]

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1. Research Center for Quantum Information Science, Tamagawa University 6-1-1, Tamagawa-gakuen, Machida, Tokyo, 194-8610 (Japan)

We investigate the Yuen 2000 (so-called Y-00)-protocol, which can realize a randomized stream cipher with high bit rate (Gbit/s) for long distances (several hundreds km). The randomized stream cipher with randomization by quantum noise based on the Y-00 protocol is called a quantum stream cipher in this paper, and it may have security against known plaintext attacks which has no analog with any conventional symmetric key ciphers. We present a simple cryptanalysis based on an attacker's heterodyne measurement and a quantum unambiguous measurement to make clear the strength of the Y-00 protocol in real communication. In addition, we give a design for the implementation of an intensity-modulation scheme and report an experimental demonstration of 1 Gbit/s quantum stream cipher through a 20-km-long transmission line.

• OSTI ID: 20718094
• Journal Information: Physical Review. A, Vol. 72, Issue 2; Other Information: DOI: 10.1103/PhysRevA.72.022335; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
DATA TRANSMISSION
DETECTION
DISTANCE
IMPLEMENTATION
MODULATION
NOISE
QUANTUM CRYPTOGRAPHY
QUANTUM MECHANICS
SECRECY PROTECTION