Abstract

Symmetric coherent states are of interest in quantum cryptography, since for such states there is an upper bound for unambiguous state discrimination (USD) probability, which is used to resist USD attack. But it is not completely clear what an eavesdropper can do for shorter channel length, when USD attack in not available. We consider the task of generalized discrimination between symmetric coherent states and construct an operation which enlarges the information content of the states with fixed failure probability. We apply this transformation to develop a zero-error eavesdropping strategy for quantum cryptography on symmetric coherent states.

中文翻译：

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量子密码学中用于监听的对称相干态之间的广义判别

摘要

对称相干态在量子密码学中非常重要，因为对于此类态，存在明确的状态鉴别（USD）概率上限，该概率用于抵御USD攻击。但是，当美元攻击不可用时，窃听者可以为更短的信道长度做什么呢？我们考虑对称相干状态之间的广义区分的任务，并构造一个以固定的失败概率扩大状态信息内容的运算。我们应用此变换为对称相干态上的量子密码学开发零错误窃听策略。