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arXiv · 2309.11073

Privacy Amplification Against Quantum Side Information Via Regular Random Binning

Yu-Chen Shen·Li Gao·Hao-Chung Cheng
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Abstract

We consider privacy amplification against quantum side information by using regular random binning as an effective extractor. For constant-type sources, we obtain error exponent and strong converse bounds in terms of the so-called quantum Augustin information. Via type decomposition, we then recover the error exponent for independent and identically distributed sources proved by Dupuis [arXiv:2105.05342]. As an application, we obtain an achievable secrecy exponent for classical-quantum wiretap channel coding in terms of the Augustin information, which solves an open problem in [IEEE Trans.~Inf.~Theory, 65(12):7985, 2019]. Our approach is to establish an operational equivalence between privacy amplification and quantum soft covering; this may be of independent interest.

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Yu-Chen Shen, Li Gao, Hao-Chung Cheng. 2023-09-20. Privacy Amplification Against Quantum Side Information Via Regular Random Binning. https://arxiv.org/abs/2309.11073

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