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Quantum partial teleportation as optimal cloning at a distance

Radim Filip
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Abstract

We propose a feasible scheme of conditional quantum partial teleportation of a qubit as optimal asymmetric cloning at a distance. In this scheme, Alice preserves one imperfect clone whereas other clone is teleported to Bob. Fidelities of the clones can be simply controlled by an asymmetry in Bell-state measurement. The optimality means that tightest inequality for the fidelities in the asymmetric cloning is saturated. Further we design a conditional teleportation as symmetric optimal N-> N+1 cloning from N Alice's replicas on single distant clone. We shortly discussed two feasible experimental implementations, first one for teleportation of polarization state of a photon and second one, for teleportation of a time-bin qubit.

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Radim Filip. 2004-01-08. Quantum partial teleportation as optimal cloning at a distance. https://doi.org/10.1103/physreva.69.052301

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