Remote Information Concentration Based on the1 → 2 OptimalUniversal AsymmetricTelecloning of Two-qubit States

The previous protocols of remote quantum information concentration were mainlyfocused on the reverse process of quantum telecloning of single-qubit states. We hereinvestigate the reverse process of 1 → 2 optimal universal asymmetric telecloning of two-qubitstates. It is shown that the quantum information originally distributed into two pairsof spatially separated observers from two senders situated at two different locations via1 → 2 optimal universal asymmetric telecloning procedure can be remotely concentratedback to a pair of different receivers with a certain probability by utilizing maximally andnon-maximally eight-particle cluster state as quantum channels, respectively.