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arXiv · 1007.1696

Coherent pulse position modulation quantum cipher supported by secret key

Masaki Sohma·Osamu Hirota
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Abstract

A quantum cipher supported by a secret key so called keyed communication in quantum noise (KCQ) is very attractive in implementing high speed key generation and secure data transmission. However, Yuen-2000 as a basic model of KCQ has a difficulty to ensure the quantitative security evaluation because all physical parameter for the cipher system is finite. Recently, an outline of a generalized scheme so called coherent pulse position modulation(CPPM) to show the rigorous security analysis is given, where the parameters are allowed to be asymptotical. This may open a new way for the quantum key distribution with coherent states of considerable energy and high speed. In this paper, we clarify a generation method of CPPM quantum signal by using a theory of unitary operator and symplectic transformation, and show an asymptotic property of security and its numerical examples.

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Masaki Sohma, Osamu Hirota. 2010-07-10. Coherent pulse position modulation quantum cipher supported by secret key. https://arxiv.org/abs/1007.1696

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