Abstract

We consider the notion of conditional entropy in hybrid (quantum-classical) systems and prove some of its properties. As an application we estimate the capacity of a measurement channel augmented by quantum feedback. We also refine the proof of the coding theorem for the entanglement-assisted classical capacity of the measurement channel with arbitrary output alphabet given in [1, 2].

中文翻译：

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关于量子测量信道纠缠辅助编码定理的证明

摘要

我们考虑了混合（量子经典）系统中条件熵的概念并证明了它的一些性质。作为一个应用程序，我们估计由量子反馈增强的测量通道的容量。我们还用 [1, 2] 中给出的任意输出字母表改进了测量通道的纠缠辅助经典容量的编码定理的证明。