AIP conference proceedings

Influence of the Correlation by Beam Splitting in YK Protocol QKD System

Masao Osaki

Published Jan 1, 2004• 0 citations

Abstract

The quantum key distribution (QKD) system can provide the absolutely secure communication for distant users [C. H. Bennett and G. Brassard, Proc. of the IEEE Int. Conf. on Computers, Systems, and Signal Processing, pp. 175–179, 1984]. But it requires single photon sources, highly sensitive detectors, and newly constructed quantum channel between the legitimate users. On the other hand, classical (or quantum) noise based key distribution system is one of the candidates to realize the key distribution system with today’s technology [U. M. Maurer, IEEE Trans. Inform. Theory, 39, No.3, pp.733–742, 1993, H. P. Yuen and A. M. Kim, Phys. Lett. A, 241, pp.135–138, 1998]. In such a system, the independence of the noise between a legitimate receiver and an eavesdropper is presupposed. For long haul distant communication, however, amplification of the carrier is indispensable. This amplification process generates correlated fluctuations between them.We analyze how much correlation occurs when a coherent state is amplified and split. Then, the influence on the security level is shown in contrast to the non correlated case.

DOI: 10.1063/1.1834447

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