Feasibility of continuous-variable quantum key distribution with noisy coherent states

Journal Article · Mon Feb 15 04:00:00 EST 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.022318· OSTI ID:21408208

Usenko, Vladyslav C ^[1]; Filip, Radim ^[2]

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1. Bogolyubov Institute for Theoretical Physics of National Academy of Sciences, U-03680 Kiev (Ukraine)
2. Department of Optics, Palacky University, CZ-772 07 Olomouc (Czech Republic)

We address security of the quantum key distribution scheme based on the noisy modulation of coherent states and investigate how it is robust against noise in the modulation regardless of the particular technical implementation. As the trusted preparation noise is shown to be security breaking even for purely lossy channels, we reveal the essential difference between two types of trusted noise, namely sender-side preparation noise and receiver-side detection noise, the latter being security preserving. We consider the method of sender-side state purification to compensate the preparation noise and show its applicability in the realistic conditions of channel loss, untrusted channel excess noise, and trusted detection noise. We show that purification makes the scheme robust to the preparation noise (i.e., even the arbitrary noisy coherent states can in principle be used for the purpose of quantum key distribution). We also take into account the effect of realistic reconciliation and show that the purification method is still efficient in this case up to a limited value of preparation noise.

• OSTI ID: 21408208
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 81; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANNIHILATION OPERATORS
DETECTION
EIGENSTATES
MATHEMATICAL OPERATORS
MODULATION
NOISE
QUANTUM OPERATORS