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, under the purified distance, 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：刻画量子信道模拟所需的最小通信量是量子信息理论中的一项基本任务。本文证明，在净化距离下，无需使用de Finetti约化技术，量子信道模拟可直接通过量子态分裂实现，并由此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反向香农定理。