Classical-Quantum Channel Resolvability Using Matrix Multiplicative Weight Update Algorithm
Koki Takahashi, Shun Watanabe
TL;DR
The paper addresses classical-quantum channel resolvability and proposes a deterministic coding approach based on the matrix MWU (MMWU) algorithm. By interpreting resolvability as a two-player game and employing quantum hypergraph soft covering, it derives single-shot, fixed-type, and i.i.d. resolvability results, showing that the achievable rate equals the Holevo capacity $C(W)$. It provides explicit codebook size scalings, establishing a deterministic alternative to random coding for C-Q resolvability with provable error guarantees. The work strengthens the connection between resolvability and quantum soft-covering techniques and has implications for secure and efficient quantum communications.
Abstract
We study classical-quantum (C-Q) channel resolvability. C-Q channel resolvability has been proved by only random coding in the literature. In our previous study, we proved channel resolvability by deterministic coding, using multiplicative weight update algorithm. We extend this approach to C-Q channels and prove C-Q channel resolvability by deterministic coding, using the matrix multiplicative weight update algorithm. This is the first approach to C-Q channel resolvability using deterministic coding.
