2 Remarks on the classical capacity of quantum channel ∗
نویسنده
چکیده
A direct proof of the relation between the one-shot classical capacity and the minimal output entropy for covariant quantum channels is suggested. The structure of covariant channels is described in some detail. A simple proof of a general inequality for entanglement-assisted classical capacity is given. 1. Let Φ be a quantum channel in a Hilbert space H of finite dimension-ality d, ¯ C (1) (Φ) – its one-shot classical capacity defined as ¯ C (1) (Φ) = max
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