Economical phase-covariant quantum telecloning of a single polarization photon via quantum nondemolition detection

We firstly investigate the quantum network for 1 → 2 economical optimal phase-covariant telecloning (EPCTC). The network is used for generating two optimal copies of a single-qubit phase-covariant state from a sender (Alice) to a remote receiver (Bob). By utilizing the quantum non-demolitions (QNDs) based on the weak cross-Kerr nonlinearities, we secondly propose an experimental scheme for realizing the 1 → 2 EPCTC of a single-photon phase-covariant state. In the experimental scheme after Alice performing a QND measurement on the to-be-cloned photon and one channel photon, Bob gets two optimal copies by performing appropriate single-photon or two-photon operations according to the outcomes of the QND measurement. Specifically, if the to-be-cloned state is on the equator, the two copies can be in two different places because only single-qubit operations are needed in this case.