2019/03/08 by Hayata Yamasaki, Mio Murao, Yamasaki, Hayata +1
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.1903.03619
openalex publication_date 2019/03/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We prove the difference between the minimal entanglement costs in quantum state merging under one-way and two-way communication in a one-shot scenario, whereas they have been known to coincide asymptotically. While the minimal entanglement cost in state merging under one-way communication is conventionally interpreted to characterize partial quantum information conditioned by quantum side information, we introduce a notion of spread quantum information evaluated by the corresponding cost under two-way communication. Spread quantum information quantitatively characterizes how nonlocally one-shot quantum information is spread, and it cannot be interpreted as partial quantum information.