可降解信道量子容量的“相当强”逆定理
量子物理
2013-12-24 v3 信息论
math.IT
摘要
我们展示了一条通向可降解信道量子容量强逆定理的可能路径。特别地,我们证明所有可降解信道都遵循我们所谓的“相当强”逆定理:当码率增加到超过量子容量时,保真度渐近地从 1 不连续跳变至至多 0.707。对于私有(经典)容量可以证明类似的结果。此外,我们可以证明,如果强逆定理对对称信道(其量子容量为零)成立,那么可降解信道就遵循强逆定理:上述在量子容量处保真度的渐近跳变则是从 1 降至 0。
引用
@article{arxiv.1301.4927,
title = {"Pretty strong" converse for the quantum capacity of degradable channels},
author = {Ciara Morgan and Andreas Winter},
journal= {arXiv preprint arXiv:1301.4927},
year = {2013}
}
备注
17 pages, requires IEEEtran.cls. v2 has new title and updated references; several small errors are corrected and some explanations expanded. v3 is final version accepted by journal; improved presentation, more references and a few more typos corrected