collaborators

6 papers

quant-ph2026

Strong Converse Exponent of Quantum State Merging

Mario Berta, Hao-Chung Cheng, Roberto Rubboli +1

We determine the strong converse exponent for the entanglement cost of quantum state merging, showing that it is characterized by the optimized - conditional Rényi entropies…

quant-ph2026

Sharp Continuity of Petz and Sandwiched Rényi Conditional Entropies

Hao-Chung Cheng, Po-Chieh Liu

We determine the sharp modulus of continuity, in trace distance, of the optimized Petz and sandwiched Rényi conditional entropies for every order . If two bipartit…

quant-ph2026

Superadditivity for Entanglement-Assisted Communication

Hao-Chung Cheng, Mario Berta

The entanglement-assisted capacity of a quantum channel admits an additive single-letter characterization, implying that joint encodings across channel uses cannot increase the ult…

quant-ph2026

Device-independent Quantum Key Distribution in the commuting operator framework

Gereon Koßmann, René Schwonnek, Po-Chieh Liu +1

Device-independent quantum key distribution (DIQKD) is arguably the gold standard for secure quantum communication, as it aims to rely only on observed input-output statistics of a…

quant-ph2026

Multiple Quantum Hypothesis Testing: One-Shot Pairwise Bounds and Sharp Asymptotics

Hao-Chung Cheng, Po-Chieh Liu

We consider Bayesian discrimination among multiple quantum states and establish a dimension-free one-shot upper bound on the minimum probability of error in terms of the sum of pai…

cs.IT2024

Exponents for Shared Randomness-Assisted Channel Simulation

Aadil Oufkir, Michael X. Cao, Hao-Chung Cheng +1

We determine the exact error and strong converse exponents of shared randomness-assisted channel simulation in worst case total-variation distance. Namely, we find that these expon…