Characterizing the minimal communication needed for the quantum channel simulation is a fundamental task in the quantum information theory. In this paper, we show that, in fidelity, the quantum channel simulation can be directly achieved via quantum state splitting without using a technique known as the de~Finetti reduction, and thus provide a pair of tighter one-shot bounds. Using the bounds, we also recover the quantum reverse Shannon theorem in a much simpler way.

翻译：量子信道模拟所需的最小通信量刻画是量子信息论中的一个基本任务。本文证明，在保真度意义下，量子信道模拟可直接通过量子态分割实现，而无需借助称为德·芬内蒂约化的技术，从而给出了一对更紧的单次界。利用这些界，我们还以更简洁的方式重新推导了量子逆香农定理。