Assisted cloning of arbitrary unknown multi-qudit state

In this paper, we propose a scheme that one can realize quantum cloning of an unknown multi-qudit state with assistance offered by a state preparer. Our scheme includes two parties: teleportation and assisted cloning. In order to complete the purpose, one multi-qudit state teleportation at the cloner´s site via k entangled pairs as the quantum channel. After the teleportation, the state preparer Victor performs one unitary transformation and one multi-qudit measurement and informs Alice of his outcome to copy the original state. Compared with existing ones in the literature, our scheme generalize assisted cloning scheme to the case of arbitrary multi-qudit state, in the meantime, we also ensure high security of our scheme.