We discuss some applications of a result on the convex combination of the quantum states (that we refer to as convex-split technique) and its variants. In the framework of Quantum Resource theory, we provide an operational way of characterizing the amount of resource in a given quantum state, for a large class of resource theories. Our results use the convex-split technique in the achievability proof, with a matching converse in the one-shot setting. Building upon the ideas involved in this achievability proof, we show how the technique (and its close counterpart of position-based decoding) can lead to a large family of entanglement-assisted protocols for quantum communication. We sketch close connections between these protocols and the port-based teleportation scheme of Ishizaka and Hiroshima [Phys. Rev. Lett. 101, 240501]. We exploit these connections to obtain a new protocol for entanglement assisted point to point quantum channel coding in the asymptotic and i.i.d. setting, with the rate of entanglement cost and achievable communication matching that of Bennett et. al. [IEEE Trans. Inf. Theory, 48, 2002]. Based on the works arXiv:1410.3031, arXiv:1708.00381, arXiv:1702.01940.
