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arXiv · 1801.03656

Quantum Encryption and Generalized Quantum Shannon Impossibility

Ching-Yi Lai·Kai-Min Chung
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Abstract

The famous Shannon impossibility result says that any encryption scheme with perfect secrecy requires a secret key at least as long as the message. In this paper we provide its quantum analogue with imperfect secrecy and imperfect correctness. We also give a systematic study of information-theoretically secure quantum encryption with two secrecy definitions. We show that the weaker one implies the stronger but with a security loss in $d$, where $d$ is the dimension of the encrypted quantum system. This is good enough if the target secrecy error is of $o(d^{-1})$.

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BibTeXRIS

Ching-Yi Lai, Kai-Min Chung. 2018-01-11. Quantum Encryption and Generalized Quantum Shannon Impossibility. https://doi.org/10.1007/s10623-018-00597-3

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