3 papers
quant-ph2026
Strong Converse Exponents of Quantum Soft Covering and Privacy Amplification
Shi-Bing Li, Hongsen Qiu, Xinyu Zhang
We determine the exact strong converse exponent of quantum soft covering under the sandwiched R{é}nyi divergence for all orders . For $α\in[\frac{1}{2},1)…
quant-ph2026
Reliability Functions of Quantum Soft Covering and Privacy Amplification via a Mixed-Order Rényi Divergence
Shi-Bing Li, Hongsen Qiu, Xinyu Zhang
In this paper, we introduce a novel mixed-order Rényi divergence and investigate its fundamental properties. Using this divergence, we define a family of mixed-order order-two Rény…
cs.IT2026
Smoothing Exponents and Decoupling in Semifinite von Neumann Algebras
Zhiwen Lin, Hongsen Qiu, Xinyu Zhang
We study the smoothing exponent of the max-relative entropy in semifinite von Neumann algebras. Our main result gives an exact exponent formula in this setting. The proof develops…