activity
20242026
collaborators

10 papers

quant-ph2026

Error Exponents for Quantum Packing Problems via An Operator Layer Cake Theorem

Hao-Chung Cheng, Po-Chieh Liu

In this work, we prove a one-shot random coding bound for classical-quantum channel coding, a problem conjectured by Burnashev and Holevo in 1998. By choosing the optimal input dis…

math.NT2026

On the geometry of the second Lagrange spectra

Hao Cheng, Harold Erazo, Carlos Gustavo Moreira +1

The Lagrange spectrum is the set of finite values of the best approximation constants , where $α\in \mathbb{R}\setminus \math…

quant-ph2026

A Mirror-Descent Algorithm for Computing the Petz-Rényi Capacity of Classical-Quantum Channels

Yu-Hong Lai, Hao-Chung Cheng

We study the computation of the -Rényi capacity of a classical-quantum (c-q) channel for . We propose an exponentiated-gradient (mirror descent) iteration that gen…

quant-ph2026

Adversarial Hypothesis Testing for Quantum Channels

Masahito Hayashi, Hao-Chung Cheng, Li Gao

This paper presents a systematic study of adversarial hypothesis testing for both quantum-quantum (QQ) and classical-quantum (CQ) channels. Unlike conventional channel discriminati…

quant-ph2025

The operator layer cake theorem is equivalent to Frenkel's integral formula

Hao-Chung Cheng, Gilad Gour, Ludovico Lami +1

The operator layer cake theorem provides an integral representation for the directional derivative of the operator logarithm in terms of a family of projections [arXiv:2507.06232].…

quant-ph2025

Global Coherence in Quantum Discord as a Resource

Chellasamy Jebarathinam, Huan-Yu Ku, Hao-Chung Cheng +1

This work addresses which aspect of \textit{bipartite coherence} in \textit{quantum discord} is essential for \textit{genuinely quantum correlation}. To this end, \textit{global co…