Entanglement assistance can improve communication rates significantly. Yet, its generation is susceptible to failure. The unreliable assistance model accounts for those challenges. Previous work provided an asymptotic formula that outlines the tradeoff between the unassisted and excess rates from entanglement assistance. We derive a full characterization for entanglement-breaking channels, and show that combining entanglement-assisted and unassisted coding is suboptimal. From a networking perspective, this finding is nontrivial and highlights a quantum behavior arising from superposition.

翻译：纠缠辅助可显著提高通信速率，但其生成过程易受失败影响。不可靠辅助模型正是针对这些挑战而提出的。先前的研究给出了一个渐近公式，概述了无辅助速率与纠缠辅助带来的额外速率之间的权衡。我们针对纠缠破坏信道推导出了完整的表征，并表明结合纠缠辅助编码与无辅助编码并非最优方案。从网络角度来看，这一发现具有非平凡性，并突显了由叠加效应产生的量子行为。