Universal purification of quantum resources in the resource theory of communication

An interesting question that recently emerged in the context of quantum resource theories is whether there exists a universal way to improve the quality of quantum resources, regardless of the inputs that are given. In previous works, it was shown that universal entanglement purification is impossible with local operation and classical communication, and that universal state purification is impossible with classical simulable operations. In this work, we show that universal resource purfication is in fact possible in the resource theory of communication. Moreover, we show that such universal purification can be realized though an entanglement-assisted protocol. For arbitrary input channels above a trivial fidelity threshold, our entanglement-assisted protocol probabilitically produces a channel whose teleportation fidelity exceeds that of all input channels. This work invites further research on the problem of universal resource purification, as well as applications of our entanglement-assisted protocol.